diff --git a/doc/source/whatsnew/v1.1.2.rst b/doc/source/whatsnew/v1.1.2.rst
index b0d375a52f8ac..c74976b14e814 100644
--- a/doc/source/whatsnew/v1.1.2.rst
+++ b/doc/source/whatsnew/v1.1.2.rst
@@ -17,6 +17,7 @@ Fixed regressions
 - Regression in :meth:`DatetimeIndex.intersection` incorrectly raising ``AssertionError`` when intersecting against a list (:issue:`35876`)
 - Fix regression in updating a column inplace (e.g. using ``df['col'].fillna(.., inplace=True)``) (:issue:`35731`)
 - Performance regression for :meth:`RangeIndex.format` (:issue:`35712`)
+- Regression in :meth:`DataFrame.replace` where a ``TypeError`` would be raised when attempting to replace elements of type :class:`Interval` (:issue:`35931`)
 -
 
 .. ---------------------------------------------------------------------------
diff --git a/pandas/_libs/interval.pyx b/pandas/_libs/interval.pyx
index 6867e8aba7411..40bd5ad8f5a1f 100644
--- a/pandas/_libs/interval.pyx
+++ b/pandas/_libs/interval.pyx
@@ -358,6 +358,11 @@ cdef class Interval(IntervalMixin):
             self_tuple = (self.left, self.right, self.closed)
             other_tuple = (other.left, other.right, other.closed)
             return PyObject_RichCompare(self_tuple, other_tuple, op)
+        elif util.is_array(other):
+            return np.array(
+                [PyObject_RichCompare(self, x, op) for x in other],
+                dtype=bool,
+            )
 
         return NotImplemented
 
diff --git a/pandas/tests/frame/methods/test_replace.py b/pandas/tests/frame/methods/test_replace.py
index 8603bff0587b6..83dfd42ae2a6e 100644
--- a/pandas/tests/frame/methods/test_replace.py
+++ b/pandas/tests/frame/methods/test_replace.py
@@ -1581,3 +1581,10 @@ def test_replace_with_compiled_regex(self):
         result = df.replace({regex: "z"}, regex=True)
         expected = pd.DataFrame(["z", "b", "c"])
         tm.assert_frame_equal(result, expected)
+
+    def test_replace_intervals(self):
+        # https://github.com/pandas-dev/pandas/issues/35931
+        df = pd.DataFrame({"a": [pd.Interval(0, 1), pd.Interval(0, 1)]})
+        result = df.replace({"a": {pd.Interval(0, 1): "x"}})
+        expected = pd.DataFrame({"a": ["x", "x"]})
+        tm.assert_frame_equal(result, expected)
diff --git a/pandas/tests/scalar/interval/test_arithmetic.py b/pandas/tests/scalar/interval/test_arithmetic.py
index 5252f1a4d5a24..b4c2b448e252a 100644
--- a/pandas/tests/scalar/interval/test_arithmetic.py
+++ b/pandas/tests/scalar/interval/test_arithmetic.py
@@ -45,3 +45,15 @@ def test_numeric_interval_add_timedelta_raises(interval, delta):
 
     with pytest.raises((TypeError, ValueError), match=msg):
         delta + interval
+
+
+@pytest.mark.parametrize("klass", [timedelta, np.timedelta64, Timedelta])
+def test_timdelta_add_timestamp_interval(klass):
+    delta = klass(0)
+    expected = Interval(Timestamp("2020-01-01"), Timestamp("2020-02-01"))
+
+    result = delta + expected
+    assert result == expected
+
+    result = expected + delta
+    assert result == expected
diff --git a/pandas/tests/scalar/interval/test_interval.py b/pandas/tests/scalar/interval/test_interval.py
index a0151bb9ac7bf..8ad9a2c7a9c70 100644
--- a/pandas/tests/scalar/interval/test_interval.py
+++ b/pandas/tests/scalar/interval/test_interval.py
@@ -2,6 +2,7 @@
 import pytest
 
 from pandas import Interval, Period, Timedelta, Timestamp
+import pandas._testing as tm
 import pandas.core.common as com
 
 
@@ -267,3 +268,11 @@ def test_constructor_errors_tz(self, tz_left, tz_right):
             msg = "left and right must have the same time zone"
         with pytest.raises(error, match=msg):
             Interval(left, right)
+
+    def test_equality_comparison_broadcasts_over_array(self):
+        # https://github.com/pandas-dev/pandas/issues/35931
+        interval = Interval(0, 1)
+        arr = np.array([interval, interval])
+        result = interval == arr
+        expected = np.array([True, True])
+        tm.assert_numpy_array_equal(result, expected)