diff --git a/Lib/test/test_ctypes/test_numbers.py b/Lib/test/test_ctypes/test_numbers.py
index f67cdf5f7d4e945..0e29cc141892e88 100644
--- a/Lib/test/test_ctypes/test_numbers.py
+++ b/Lib/test/test_ctypes/test_numbers.py
@@ -69,6 +69,11 @@ def test_default_init(self):
         for t in signed_types + unsigned_types + float_types:
             self.assertEqual(t().value, 0)
 
+    def test_resized_scalar_value(self):
+        value = c_int(17)
+        ctypes.resize(value, 65536)
+        self.assertEqual(value.value, 17)
+
     def test_unsigned_values(self):
         # the value given to the constructor is available
         # as the 'value' attribute
diff --git a/Misc/NEWS.d/next/Library/2026-10-19-20-38-17.gh-issue-159739.08caa7.rst b/Misc/NEWS.d/next/Library/2026-10-19-20-38-17.gh-issue-159739.08caa7.rst
new file mode 100644
index 000000000000000..3574193b51f343e
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-10-19-20-38-17.gh-issue-159739.08caa7.rst
@@ -0,0 +1,2 @@
+Fix incorrect :mod:`ctypes` scalar values after :func:`ctypes.resize` enlarges
+the object.
diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
index 43f416c141fd8ad..8ce6bd38882fc87 100644
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -5456,7 +5456,7 @@ _ctypes_Simple_value_get_impl(CDataObject *self)
     assert(info); /* Cannot be NULL for CDataObject instances */
     assert(info->getfunc);
     PyObject *res;
-    res = info->getfunc(self->b_ptr, self->b_size);
+    res = info->getfunc(self->b_ptr, info->size);
     return res;
 }