diff --git a/Lib/ctypes/util.py b/Lib/ctypes/util.py
index 99504911a3dbe0..2aec2bd166ea84 100644
--- a/Lib/ctypes/util.py
+++ b/Lib/ctypes/util.py
@@ -173,6 +173,28 @@ def find_library(name):
 fname = f"{directory}/lib{name}.so"
 return fname if os.path.isfile(fname) else None
 
+elif sys.platform == "emscripten":
+ def _is_wasm(filename):
+ # Return True if the given file is an WASM module
+ wasm_header = b"\x00asm"
+ with open(filename, 'br') as thefile:
+ return thefile.read(4) == wasm_header
+
+ def find_library(name):
+ candidates = [f"lib{name}.so", f"lib{name}.wasm"]
+ paths = os.environ.get("LD_LIBRARY_PATH", "")
+ for libdir in paths.split(":"):
+ for name in candidates:
+ libfile = os.path.join(libdir, name)
+
+ if os.path.isfile(libfile):
+ if not _is_wasm(libfile):
+ continue
+
+ return libfile
+
+ return None
+
 elif os.name == "posix":
 # Andreas Degert's find functions, using gcc, /sbin/ldconfig, objdump
 import re, tempfile
diff --git a/Lib/test/test_ctypes/test_find.py b/Lib/test/test_ctypes/test_find.py
index 3bd41a0e435d91..ca7f233784b1d9 100644
--- a/Lib/test/test_ctypes/test_find.py
+++ b/Lib/test/test_ctypes/test_find.py
@@ -153,5 +153,37 @@ def test_find(self):
 self.assertIsNone(find_library(name))
 
 
+@unittest.skipUnless(test.support.is_emscripten,
+ 'Test only valid for Emscripten')
+class FindLibraryEmscripten(unittest.TestCase):
+ def test_find_on_libpath(self):
+ import tempfile
+
+ # A very simple wasm module
+ # In WAT format: (module)
+ wasm_module = b'\x00asm\x01\x00\x00\x00\x00\x08\x04name\x02\x01\x00'
+
+ with tempfile.TemporaryDirectory() as d:
+ libname = 'dummy'
+ dstname = os.path.join(d, 'lib%s.so' % libname)
+ with open(dstname, 'wb') as f:
+ f.write(wasm_module)
+
+ # now check that the .so can't be found (since not in
+ # LD_LIBRARY_PATH)
+ self.assertIsNone(find_library(libname))
+ # now add the location to LD_LIBRARY_PATH
+ with os_helper.EnvironmentVarGuard() as env:
+ KEY = 'LD_LIBRARY_PATH'
+ if KEY not in env:
+ v = d
+ else:
+ v = '%s:%s' % (env[KEY], d)
+ env.set(KEY, v)
+ # now check that the .so can be found (since in
+ # LD_LIBRARY_PATH)
+ self.assertEqual(find_library(libname), dstname)
+
+
 if __name__ == "__main__":
 unittest.main()
diff --git a/Misc/NEWS.d/next/Library/2025-09-05-05-53-43.gh-issue-99948.KMSlG6.rst b/Misc/NEWS.d/next/Library/2025-09-05-05-53-43.gh-issue-99948.KMSlG6.rst
new file mode 100644
index 00000000000000..46e6dfad1cd5d8
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-09-05-05-53-43.gh-issue-99948.KMSlG6.rst
@@ -0,0 +1 @@
+:func:`ctypes.util.find_library` now works in Emscripten build.
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