diff --git a/doc/redirects.csv b/doc/redirects.csv
index d0f4ae331f7e3..a1d3207033057 100644
--- a/doc/redirects.csv
+++ b/doc/redirects.csv
@@ -671,7 +671,6 @@ generated/pandas.Index.is_integer,../reference/api/pandas.Index.is_integer
 generated/pandas.Index.is_interval,../reference/api/pandas.Index.is_interval
 generated/pandas.Index.is_lexsorted_for_tuple,../reference/api/pandas.Index.is_lexsorted_for_tuple
 generated/pandas.Index.is_monotonic_decreasing,../reference/api/pandas.Index.is_monotonic_decreasing
-generated/pandas.Index.is_monotonic,../reference/api/pandas.Index.is_monotonic
 generated/pandas.Index.is_monotonic_increasing,../reference/api/pandas.Index.is_monotonic_increasing
 generated/pandas.Index.isna,../reference/api/pandas.Index.isna
 generated/pandas.Index.isnull,../reference/api/pandas.Index.isnull
@@ -1068,7 +1067,6 @@ generated/pandas.Series.interpolate,../reference/api/pandas.Series.interpolate
 generated/pandas.Series.is_copy,../reference/api/pandas.Series.is_copy
 generated/pandas.Series.isin,../reference/api/pandas.Series.isin
 generated/pandas.Series.is_monotonic_decreasing,../reference/api/pandas.Series.is_monotonic_decreasing
-generated/pandas.Series.is_monotonic,../reference/api/pandas.Series.is_monotonic
 generated/pandas.Series.is_monotonic_increasing,../reference/api/pandas.Series.is_monotonic_increasing
 generated/pandas.Series.isna,../reference/api/pandas.Series.isna
 generated/pandas.Series.isnull,../reference/api/pandas.Series.isnull
diff --git a/doc/source/reference/indexing.rst b/doc/source/reference/indexing.rst
index b7866a0076d84..af4130f2e8961 100644
--- a/doc/source/reference/indexing.rst
+++ b/doc/source/reference/indexing.rst
@@ -25,7 +25,6 @@ Properties
    :toctree: api/
 
    Index.values
-   Index.is_monotonic
    Index.is_monotonic_increasing
    Index.is_monotonic_decreasing
    Index.is_unique
diff --git a/doc/source/reference/series.rst b/doc/source/reference/series.rst
index c9604f48dd334..c8bbe922f5313 100644
--- a/doc/source/reference/series.rst
+++ b/doc/source/reference/series.rst
@@ -167,7 +167,6 @@ Computations / descriptive stats
    Series.unique
    Series.nunique
    Series.is_unique
-   Series.is_monotonic
    Series.is_monotonic_increasing
    Series.is_monotonic_decreasing
    Series.value_counts
diff --git a/doc/source/whatsnew/v2.0.0.rst b/doc/source/whatsnew/v2.0.0.rst
index d71160cdbc369..e68f5aa074229 100644
--- a/doc/source/whatsnew/v2.0.0.rst
+++ b/doc/source/whatsnew/v2.0.0.rst
@@ -265,6 +265,7 @@ Removal of prior version deprecations/changes
 - Removed :func:`is_extension_type` in favor of :func:`is_extension_array_dtype` (:issue:`29457`)
 - Removed ``.ExponentialMovingWindow.vol`` (:issue:`39220`)
 - Removed :meth:`Index.get_value` and :meth:`Index.set_value` (:issue:`33907`, :issue:`28621`)
+- Removed :meth:`Series.is_monotonic` and :meth:`Index.is_monotonic` in favor of :meth:`Series.is_monotonic_increasing` and :meth:`Index.is_monotonic_increasing` (:issue:`45422`)
 - Removed :meth:`Series.slice_shift` and :meth:`DataFrame.slice_shift` (:issue:`37601`)
 - Remove :meth:`DataFrameGroupBy.pad` and :meth:`DataFrameGroupBy.backfill` (:issue:`45076`)
 - Remove ``numpy`` argument from :func:`read_json` (:issue:`30636`)
diff --git a/pandas/core/base.py b/pandas/core/base.py
index 2145ecd10a7b0..afcab23e130cd 100644
--- a/pandas/core/base.py
+++ b/pandas/core/base.py
@@ -17,7 +17,6 @@
     final,
     overload,
 )
-import warnings
 
 import numpy as np
 
@@ -38,7 +37,6 @@
     cache_readonly,
     doc,
 )
-from pandas.util._exceptions import find_stack_level
 
 from pandas.core.dtypes.common import (
     is_categorical_dtype,
@@ -1062,27 +1060,6 @@ def is_unique(self) -> bool:
         """
         return self.nunique(dropna=False) == len(self)
 
-    @property
-    def is_monotonic(self) -> bool:
-        """
-        Return boolean if values in the object are monotonically increasing.
-
-        .. deprecated:: 1.5.0
-            is_monotonic is deprecated and will be removed in a future version.
-            Use is_monotonic_increasing instead.
-
-        Returns
-        -------
-        bool
-        """
-        warnings.warn(
-            "is_monotonic is deprecated and will be removed in a future version. "
-            "Use is_monotonic_increasing instead.",
-            FutureWarning,
-            stacklevel=find_stack_level(),
-        )
-        return self.is_monotonic_increasing
-
     @property
     def is_monotonic_increasing(self) -> bool:
         """
diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index b2ea46ce1399e..ac70591032355 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -2197,24 +2197,6 @@ def _can_hold_na(self) -> bool:
             return False
         return True
 
-    @final
-    @property
-    def is_monotonic(self) -> bool:
-        """
-        Alias for is_monotonic_increasing.
-
-        .. deprecated:: 1.5.0
-            is_monotonic is deprecated and will be removed in a future version.
-            Use is_monotonic_increasing instead.
-        """
-        warnings.warn(
-            "is_monotonic is deprecated and will be removed in a future version. "
-            "Use is_monotonic_increasing instead.",
-            FutureWarning,
-            stacklevel=find_stack_level(),
-        )
-        return self.is_monotonic_increasing
-
     @property
     def is_monotonic_increasing(self) -> bool:
         """