diff --git a/doc/source/whatsnew/v1.5.0.rst b/doc/source/whatsnew/v1.5.0.rst
index af2f41284b259..50a5bf383de77 100644
--- a/doc/source/whatsnew/v1.5.0.rst
+++ b/doc/source/whatsnew/v1.5.0.rst
@@ -363,6 +363,7 @@ Other Deprecations
 - Deprecated treating all-bool ``object``-dtype columns as bool-like in :meth:`DataFrame.any` and :meth:`DataFrame.all` with ``bool_only=True``, explicitly cast to bool instead (:issue:`46188`)
 - Deprecated behavior of method :meth:`DataFrame.quantile`, attribute ``numeric_only`` will default False. Including datetime/timedelta columns in the result (:issue:`7308`).
 - Deprecated :attr:`Timedelta.freq` and :attr:`Timedelta.is_populated` (:issue:`46430`)
+- Deprecated :attr:`Timedelta.delta` (:issue:`46476`)
 -
 
 .. ---------------------------------------------------------------------------
diff --git a/pandas/_libs/tslibs/timedeltas.pyx b/pandas/_libs/tslibs/timedeltas.pyx
index fa0db6a46deef..627006a7f32c0 100644
--- a/pandas/_libs/tslibs/timedeltas.pyx
+++ b/pandas/_libs/tslibs/timedeltas.pyx
@@ -1014,6 +1014,12 @@ cdef class _Timedelta(timedelta):
         >>> td.delta
         42
         """
+        # Deprecated GH#46476
+        warnings.warn(
+            "Timedelta.delta is deprecated and will be removed in a future version.",
+            FutureWarning,
+            stacklevel=1,
+        )
         return self.value
 
     @property
diff --git a/pandas/tests/scalar/timedelta/test_timedelta.py b/pandas/tests/scalar/timedelta/test_timedelta.py
index 36520a1983aac..1ec93c69def99 100644
--- a/pandas/tests/scalar/timedelta/test_timedelta.py
+++ b/pandas/tests/scalar/timedelta/test_timedelta.py
@@ -681,3 +681,10 @@ def test_is_populated_deprecated():
 
     with pytest.raises(AttributeError, match="is not writable"):
         td.is_populated = 1
+
+
+def test_delta_deprecated():
+    # GH#46476
+    td = Timedelta(123456546, unit="ns")
+    with tm.assert_produces_warning(FutureWarning, match="Timedelta.delta is"):
+        td.delta