diff --git a/tests/test_foliumap.py b/tests/test_foliumap.py
new file mode 100644
index 0000000000..3ffe010a72
--- /dev/null
+++ b/tests/test_foliumap.py
@@ -0,0 +1,309 @@
+"""Tests for the foliumap module."""
+
+import json
+import os
+import tempfile
+import unittest
+from unittest import mock
+
+try:
+    import sys
+    import folium
+
+    _fake_basemaps = {
+        "ROADMAP": folium.TileLayer(
+            tiles="https://mt1.google.com/vt/lyrs=m&x={x}&y={y}&z={z}",
+            attr="Google",
+            name="ROADMAP",
+        ),
+        "SATELLITE": folium.TileLayer(
+            tiles="https://mt1.google.com/vt/lyrs=s&x={x}&y={y}&z={z}",
+            attr="Google",
+            name="SATELLITE",
+        ),
+        "HYBRID": folium.TileLayer(
+            tiles="https://mt1.google.com/vt/lyrs=y&x={x}&y={y}&z={z}",
+            attr="Google",
+            name="HYBRID",
+        ),
+        "TERRAIN": folium.TileLayer(
+            tiles="https://mt1.google.com/vt/lyrs=p&x={x}&y={y}&z={z}",
+            attr="Google",
+            name="TERRAIN",
+        ),
+        "OpenStreetMap": folium.TileLayer(
+            tiles="OpenStreetMap", attr="OSM", name="OpenStreetMap"
+        ),
+    }
+
+    # Importing the geemap package causes `from .geemap import *` which brings
+    # a Box named `basemaps` into the geemap namespace, shadowing the real
+    # basemaps *module*.  When foliumap.py later does `from . import basemaps`
+    # Python resolves the package attribute (the Box) instead of the module,
+    # so `basemaps.xyz_to_folium()` fails.
+    #
+    # Fix: ensure the geemap package is loaded, then temporarily restore the
+    # real basemaps module as the package attribute so foliumap's
+    # `from . import basemaps` picks up the actual module (with our mock on it).
+    import geemap
+
+    _real_basemaps_module = sys.modules["geemap.basemaps"]
+
+    # Drop any cached foliumap so the module-level code re-executes with our mock.
+    sys.modules.pop("geemap.foliumap", None)
+
+    _saved_attr = getattr(geemap, "basemaps", None)
+    geemap.basemaps = _real_basemaps_module
+
+    with mock.patch.object(
+        _real_basemaps_module, "xyz_to_folium", return_value=_fake_basemaps
+    ):
+        from geemap import foliumap
+
+    geemap.basemaps = _saved_attr
+    FOLIUM_AVAILABLE = True
+except Exception:
+    FOLIUM_AVAILABLE = False
+
+
+@unittest.skipUnless(FOLIUM_AVAILABLE, "folium not available")
+class FoliumapTest(unittest.TestCase):
+
+    def _make_map(self, **kwargs) -> foliumap.Map:
+        return foliumap.Map(ee_initialize=False, **kwargs)
+
+    def test_map_init_default_params(self):
+        m = self._make_map()
+        self.assertIsInstance(m, folium.Map)
+        self.assertEqual(m.location, [20, 0])
+        self.assertEqual(m.options["zoom"], 2)
+
+    def test_map_init_custom_center(self):
+        m = self._make_map(center=[40, -100])
+        self.assertEqual(m.location, [40, -100])
+
+    def test_map_init_custom_zoom(self):
+        m = self._make_map(zoom=10)
+        self.assertEqual(m.options["zoom"], 10)
+
+    def test_map_init_location_param(self):
+        m = self._make_map(location=[35, 139])
+        self.assertEqual(m.location, [35, 139])
+
+    def test_map_baseclass(self):
+        m = self._make_map()
+        self.assertEqual(m.baseclass, "folium")
+
+    def test_map_init_draw_features_empty(self):
+        m = self._make_map()
+        self.assertEqual(m.draw_features, [])
+        self.assertIsNone(m.draw_last_feature)
+
+    def test_map_max_zoom_default(self):
+        m = self._make_map()
+        # The default fit_bounds call uses maxZoom; verify via the FitBounds child.
+        fit_children = [
+            c for c in m._children.values() if type(c).__name__ == "FitBounds"
+        ]
+        self.assertTrue(len(fit_children) > 0)
+        self.assertEqual(fit_children[0].options.get("maxZoom"), 2)
+
+    def test_set_center_updates_bounds(self):
+        m = self._make_map()
+        m.set_center(-122.4, 37.8, zoom=12)
+        # folium stores bounds via FitBounds children, not in get_bounds().
+        fit_children = [
+            c for c in m._children.values() if type(c).__name__ == "FitBounds"
+        ]
+        last = fit_children[-1]
+        self.assertAlmostEqual(last.bounds[0][0], 37.8, places=1)
+        self.assertAlmostEqual(last.bounds[0][1], -122.4, places=1)
+
+    def test_zoom_to_bounds_updates_bounds(self):
+        m = self._make_map()
+        m.zoom_to_bounds([-122.5, 37.5, -122.0, 38.0])
+        # folium stores bounds via FitBounds children.
+        fit_children = [
+            c for c in m._children.values() if type(c).__name__ == "FitBounds"
+        ]
+        last = fit_children[-1]
+        south, west = last.bounds[0]
+        north, east = last.bounds[1]
+        self.assertAlmostEqual(south, 37.5, places=1)
+        self.assertAlmostEqual(west, -122.5, places=1)
+        self.assertAlmostEqual(north, 38.0, places=1)
+        self.assertAlmostEqual(east, -122.0, places=1)
+
+    def test_add_tile_layer_increases_children(self):
+        m = self._make_map()
+        children_before = len(m._children)
+        m.add_tile_layer(
+            tiles="https://tile.example.com/{z}/{x}/{y}.png",
+            name="Test Layer",
+            attribution="Test",
+        )
+        self.assertGreater(len(m._children), children_before)
+
+    def test_add_tile_layer_name_in_children(self):
+        m = self._make_map()
+        m.add_tile_layer(
+            tiles="https://tile.example.com/{z}/{x}/{y}.png",
+            name="MyTiles",
+            attribution="Test",
+        )
+        child_names = [
+            getattr(c, "tile_name", getattr(c, "name", ""))
+            for c in m._children.values()
+        ]
+        # The tile layer name should appear in children tile_name attributes.
+        self.assertIn("MyTiles", child_names)
+
+    def test_add_wms_layer_increases_children(self):
+        m = self._make_map()
+        children_before = len(m._children)
+        m.add_wms_layer(
+            url="https://example.com/wms",
+            layers="test_layer",
+            name="WMS Test",
+        )
+        self.assertGreater(len(m._children), children_before)
+
+    def test_add_marker_list(self):
+        m = self._make_map()
+        children_before = len(m._children)
+        m.add_marker(location=[37.8, -122.4], popup="Test")
+        self.assertGreater(len(m._children), children_before)
+
+    def test_add_marker_tuple(self):
+        m = self._make_map()
+        children_before = len(m._children)
+        m.add_marker(location=(37.8, -122.4), tooltip="Tooltip")
+        self.assertGreater(len(m._children), children_before)
+
+    def test_add_marker_invalid_type_raises(self):
+        m = self._make_map()
+        with self.assertRaises(TypeError):
+            m.add_marker(location="invalid")
+
+    def test_add_geojson_from_dict(self):
+        m = self._make_map()
+        geojson_data = {
+            "type": "FeatureCollection",
+            "features": [
+                {
+                    "type": "Feature",
+                    "geometry": {
+                        "type": "Point",
+                        "coordinates": [-122.4, 37.8],
+                    },
+                    "properties": {"name": "Test Point"},
+                }
+            ],
+        }
+        children_before = len(m._children)
+        m.add_geojson(geojson_data, layer_name="GeoJSON Test")
+        self.assertGreater(len(m._children), children_before)
+
+    def test_add_geojson_from_file(self):
+        geojson_data = {
+            "type": "FeatureCollection",
+            "features": [
+                {
+                    "type": "Feature",
+                    "geometry": {
+                        "type": "Point",
+                        "coordinates": [-122.4, 37.8],
+                    },
+                    "properties": {"name": "Test"},
+                }
+            ],
+        }
+        with tempfile.TemporaryDirectory() as tmpdir:
+            filepath = os.path.join(tmpdir, "test.geojson")
+            with open(filepath, "w") as f:
+                json.dump(geojson_data, f)
+            m = self._make_map()
+            children_before = len(m._children)
+            m.add_geojson(filepath, layer_name="File GeoJSON")
+            self.assertGreater(len(m._children), children_before)
+
+    def test_add_geojson_file_not_found_raises(self):
+        m = self._make_map()
+        with self.assertRaises(Exception):
+            m.add_geojson("/nonexistent/path.geojson")
+
+    def test_add_geojson_invalid_type_raises(self):
+        m = self._make_map()
+        with self.assertRaises(Exception):
+            m.add_geojson(12345)
+
+    def test_add_heatmap_from_list(self):
+        m = self._make_map()
+        data = [[37.8, -122.4, 1.0], [37.9, -122.3, 2.0]]
+        children_before = len(m._children)
+        m.add_heatmap(data=data, name="Heat")
+        self.assertGreater(len(m._children), children_before)
+
+    def test_add_heatmap_invalid_data_raises(self):
+        m = self._make_map()
+        with self.assertRaises(ValueError):
+            m.add_heatmap(data=12345)
+
+    def test_to_html_returns_string(self):
+        m = self._make_map()
+        html = m.to_html()
+        self.assertIsInstance(html, str)
+        self.assertIn("<html>", html.lower())
+        self.assertIn("leaflet", html.lower())
+
+    def test_to_html_saves_file(self):
+        with tempfile.TemporaryDirectory() as tmpdir:
+            filepath = os.path.join(tmpdir, "test_map.html")
+            m = self._make_map()
+            m.to_html(filepath)
+            self.assertTrue(os.path.exists(filepath))
+            with open(filepath) as f:
+                content = f.read()
+            self.assertIn("<html>", content.lower())
+            self.assertIn("leaflet", content.lower())
+
+    def test_to_html_invalid_extension_raises(self):
+        m = self._make_map()
+        with self.assertRaises(ValueError):
+            m.to_html("output.txt")
+
+    def test_add_layer_control(self):
+        m = self._make_map()
+        children_before = len(m._children)
+        m.add_layer_control()
+        self.assertGreater(len(m._children), children_before)
+
+    def test_set_control_visibility_adds_children(self):
+        m = self._make_map()
+        children_before = len(m._children)
+        m.set_control_visibility(
+            layerControl=True,
+            fullscreenControl=True,
+            latLngPopup=True,
+        )
+        self.assertGreater(len(m._children), children_before)
+
+    def test_set_options_adds_basemap(self):
+        m = self._make_map()
+        children_before = len(m._children)
+        m.setOptions("HYBRID")
+        self.assertGreater(len(m._children), children_before)
+
+    def test_set_options_invalid_basemap_raises(self):
+        m = self._make_map()
+        with self.assertRaises(Exception):
+            m.setOptions("INVALID_BASEMAP_XYZ")
+
+    def test_add_cog_mosaic_raises_not_implemented(self):
+        m = self._make_map()
+        with self.assertRaises(NotImplementedError):
+            m.add_cog_mosaic()
+
+
+if __name__ == "__main__":
+    unittest.main()