diff --git a/Lib/test/test_marshal.py b/Lib/test/test_marshal.py
index d2d6b487148..c7def9a5995 100644
--- a/Lib/test/test_marshal.py
+++ b/Lib/test/test_marshal.py
@@ -7,6 +7,11 @@ import unittest
 import os
 import types
 
+try:
+    import _testcapi
+except ImportError:
+    _testcapi = None
+
 class HelperMixin:
     def helper(self, sample, *extra):
         new = marshal.loads(marshal.dumps(sample, *extra))
@@ -434,18 +439,88 @@ class InterningTestCase(unittest.TestCase, HelperMixin):
         s2 = sys.intern(s)
         self.assertNotEqual(id(s2), id(s))
 
+@support.cpython_only
+@unittest.skipUnless(_testcapi, 'requires _testcapi')
+class CAPI_TestCase(unittest.TestCase, HelperMixin):
+
+    def test_write_long_to_file(self):
+        for v in range(marshal.version + 1):
+            _testcapi.pymarshal_write_long_to_file(0x12345678, support.TESTFN, v)
+            with open(support.TESTFN, 'rb') as f:
+                data = f.read()
+            support.unlink(support.TESTFN)
+            self.assertEqual(data, b'\x78\x56\x34\x12')
+
+    def test_write_object_to_file(self):
+        obj = ('\u20ac', b'abc', 123, 45.6, 7+8j, 'long line '*1000)
+        for v in range(marshal.version + 1):
+            _testcapi.pymarshal_write_object_to_file(obj, support.TESTFN, v)
+            with open(support.TESTFN, 'rb') as f:
+                data = f.read()
+            support.unlink(support.TESTFN)
+            self.assertEqual(marshal.loads(data), obj)
+
+    def test_read_short_from_file(self):
+        with open(support.TESTFN, 'wb') as f:
+            f.write(b'\x34\x12xxxx')
+        r, p = _testcapi.pymarshal_read_short_from_file(support.TESTFN)
+        support.unlink(support.TESTFN)
+        self.assertEqual(r, 0x1234)
+        self.assertEqual(p, 2)
+
+        with open(support.TESTFN, 'wb') as f:
+            f.write(b'\x12')
+        with self.assertRaises(EOFError):
+            _testcapi.pymarshal_read_short_from_file(support.TESTFN)
+        support.unlink(support.TESTFN)
+
+    def test_read_long_from_file(self):
+        with open(support.TESTFN, 'wb') as f:
+            f.write(b'\x78\x56\x34\x12xxxx')
+        r, p = _testcapi.pymarshal_read_long_from_file(support.TESTFN)
+        support.unlink(support.TESTFN)
+        self.assertEqual(r, 0x12345678)
+        self.assertEqual(p, 4)
+
+        with open(support.TESTFN, 'wb') as f:
+            f.write(b'\x56\x34\x12')
+        with self.assertRaises(EOFError):
+            _testcapi.pymarshal_read_long_from_file(support.TESTFN)
+        support.unlink(support.TESTFN)
+
+    def test_read_last_object_from_file(self):
+        obj = ('\u20ac', b'abc', 123, 45.6, 7+8j)
+        for v in range(marshal.version + 1):
+            data = marshal.dumps(obj, v)
+            with open(support.TESTFN, 'wb') as f:
+                f.write(data + b'xxxx')
+            r, p = _testcapi.pymarshal_read_last_object_from_file(support.TESTFN)
+            support.unlink(support.TESTFN)
+            self.assertEqual(r, obj)
+
+            with open(support.TESTFN, 'wb') as f:
+                f.write(data[:1])
+            with self.assertRaises(EOFError):
+                _testcapi.pymarshal_read_last_object_from_file(support.TESTFN)
+            support.unlink(support.TESTFN)
+
+    def test_read_object_from_file(self):
+        obj = ('\u20ac', b'abc', 123, 45.6, 7+8j)
+        for v in range(marshal.version + 1):
+            data = marshal.dumps(obj, v)
+            with open(support.TESTFN, 'wb') as f:
+                f.write(data + b'xxxx')
+            r, p = _testcapi.pymarshal_read_object_from_file(support.TESTFN)
+            support.unlink(support.TESTFN)
+            self.assertEqual(r, obj)
+            self.assertEqual(p, len(data))
+
+            with open(support.TESTFN, 'wb') as f:
+                f.write(data[:1])
+            with self.assertRaises(EOFError):
+                _testcapi.pymarshal_read_object_from_file(support.TESTFN)
+            support.unlink(support.TESTFN)
 
-def test_main():
-    support.run_unittest(IntTestCase,
-                         FloatTestCase,
-                         StringTestCase,
-                         CodeTestCase,
-                         ContainerTestCase,
-                         ExceptionTestCase,
-                         BufferTestCase,
-                         BugsTestCase,
-                         LargeValuesTestCase,
-                        )
 
 if __name__ == "__main__":
-    test_main()
+    unittest.main()
diff --git a/Misc/NEWS b/Misc/NEWS
index e05e6137ce1..25ea656b539 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -613,6 +613,8 @@ Library
 - Issue #17442: InteractiveInterpreter now displays the full chained traceback
   in its showtraceback method, to match the built in interactive interpreter.
 
+- Issue #23392: Added tests for marshal C API that works with FILE*.
+
 - Issue #10510: distutils register and upload methods now use HTML standards
   compliant CRLF line endings.
 
diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index 465826065f6..bed6568990e 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -11,6 +11,7 @@
 #include <float.h>
 #include "structmember.h"
 #include "datetime.h"
+#include "marshal.h"
 #include <signal.h>
 
 #ifdef WITH_THREAD
@@ -3199,6 +3200,159 @@ test_raise_signal(PyObject* self, PyObject *args)
     Py_RETURN_NONE;
 }
 
+/* marshal */
+
+static PyObject*
+pymarshal_write_long_to_file(PyObject* self, PyObject *args)
+{
+    long value;
+    char *filename;
+    int version;
+    FILE *fp;
+
+    if (!PyArg_ParseTuple(args, "lsi:pymarshal_write_long_to_file",
+                          &value, &filename, &version))
+        return NULL;
+
+    fp = fopen(filename, "wb");
+    if (fp == NULL) {
+        PyErr_SetFromErrno(PyExc_OSError);
+        return NULL;
+    }
+
+    PyMarshal_WriteLongToFile(value, fp, version);
+
+    fclose(fp);
+    if (PyErr_Occurred())
+        return NULL;
+    Py_RETURN_NONE;
+}
+
+static PyObject*
+pymarshal_write_object_to_file(PyObject* self, PyObject *args)
+{
+    PyObject *obj;
+    char *filename;
+    int version;
+    FILE *fp;
+
+    if (!PyArg_ParseTuple(args, "Osi:pymarshal_write_object_to_file",
+                          &obj, &filename, &version))
+        return NULL;
+
+    fp = fopen(filename, "wb");
+    if (fp == NULL) {
+        PyErr_SetFromErrno(PyExc_OSError);
+        return NULL;
+    }
+
+    PyMarshal_WriteObjectToFile(obj, fp, version);
+
+    fclose(fp);
+    if (PyErr_Occurred())
+        return NULL;
+    Py_RETURN_NONE;
+}
+
+static PyObject*
+pymarshal_read_short_from_file(PyObject* self, PyObject *args)
+{
+    int value;
+    long pos;
+    char *filename;
+    FILE *fp;
+
+    if (!PyArg_ParseTuple(args, "s:pymarshal_read_short_from_file", &filename))
+        return NULL;
+
+    fp = fopen(filename, "rb");
+    if (fp == NULL) {
+        PyErr_SetFromErrno(PyExc_OSError);
+        return NULL;
+    }
+
+    value = PyMarshal_ReadShortFromFile(fp);
+    pos = ftell(fp);
+
+    fclose(fp);
+    if (PyErr_Occurred())
+        return NULL;
+    return Py_BuildValue("il", value, pos);
+}
+
+static PyObject*
+pymarshal_read_long_from_file(PyObject* self, PyObject *args)
+{
+    long value, pos;
+    char *filename;
+    FILE *fp;
+
+    if (!PyArg_ParseTuple(args, "s:pymarshal_read_long_from_file", &filename))
+        return NULL;
+
+    fp = fopen(filename, "rb");
+    if (fp == NULL) {
+        PyErr_SetFromErrno(PyExc_OSError);
+        return NULL;
+    }
+
+    value = PyMarshal_ReadLongFromFile(fp);
+    pos = ftell(fp);
+
+    fclose(fp);
+    if (PyErr_Occurred())
+        return NULL;
+    return Py_BuildValue("ll", value, pos);
+}
+
+static PyObject*
+pymarshal_read_last_object_from_file(PyObject* self, PyObject *args)
+{
+    PyObject *obj;
+    long pos;
+    char *filename;
+    FILE *fp;
+
+    if (!PyArg_ParseTuple(args, "s:pymarshal_read_last_object_from_file", &filename))
+        return NULL;
+
+    fp = fopen(filename, "rb");
+    if (fp == NULL) {
+        PyErr_SetFromErrno(PyExc_OSError);
+        return NULL;
+    }
+
+    obj = PyMarshal_ReadLastObjectFromFile(fp);
+    pos = ftell(fp);
+
+    fclose(fp);
+    return Py_BuildValue("Nl", obj, pos);
+}
+
+static PyObject*
+pymarshal_read_object_from_file(PyObject* self, PyObject *args)
+{
+    PyObject *obj;
+    long pos;
+    char *filename;
+    FILE *fp;
+
+    if (!PyArg_ParseTuple(args, "s:pymarshal_read_object_from_file", &filename))
+        return NULL;
+
+    fp = fopen(filename, "rb");
+    if (fp == NULL) {
+        PyErr_SetFromErrno(PyExc_OSError);
+        return NULL;
+    }
+
+    obj = PyMarshal_ReadObjectFromFile(fp);
+    pos = ftell(fp);
+
+    fclose(fp);
+    return Py_BuildValue("Nl", obj, pos);
+}
+
 
 static PyMethodDef TestMethods[] = {
     {"raise_exception",         raise_exception,                 METH_VARARGS},
@@ -3346,6 +3500,18 @@ static PyMethodDef TestMethods[] = {
     {"call_in_temporary_c_thread", call_in_temporary_c_thread, METH_O,
      PyDoc_STR("set_error_class(error_class) -> None")},
 #endif
+    {"pymarshal_write_long_to_file",
+        pymarshal_write_long_to_file, METH_VARARGS},
+    {"pymarshal_write_object_to_file",
+        pymarshal_write_object_to_file, METH_VARARGS},
+    {"pymarshal_read_short_from_file",
+        pymarshal_read_short_from_file, METH_VARARGS},
+    {"pymarshal_read_long_from_file",
+        pymarshal_read_long_from_file, METH_VARARGS},
+    {"pymarshal_read_last_object_from_file",
+        pymarshal_read_last_object_from_file, METH_VARARGS},
+    {"pymarshal_read_object_from_file",
+        pymarshal_read_object_from_file, METH_VARARGS},
     {NULL, NULL} /* sentinel */
 };