diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index a60570a82e..c5421460ef 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -7,6 +7,11 @@ in development
 Changed
 ~~~~~~~
 
+* Removed --python3 deprecated flag from st2client. #5305
+
+  Contributed by Amanda McGuinness (@amanda11 Ammeon Solutions)
+
+  Contributed by @blag.
 * Fixed ``__init__.py`` files to use double quotes to better align with black linting #5299
 
   Contributed by @blag.
diff --git a/st2client/st2client/commands/pack.py b/st2client/st2client/commands/pack.py
index 8d05fc88dc..cab9774215 100644
--- a/st2client/st2client/commands/pack.py
+++ b/st2client/st2client/commands/pack.py
@@ -19,7 +19,6 @@
 
 import six
 import editor
-import warnings
 import yaml
 
 from st2client.models import Config
@@ -255,12 +254,6 @@ def __init__(self, resource, *args, **kwargs):
             help="Name of the %s in Exchange, or a git repo URL."
             % resource.get_plural_display_name().lower(),
         )
-        self.parser.add_argument(
-            "--python3",
-            action="store_true",
-            default=False,
-            help="Use Python 3 binary for pack virtual environment.",
-        )
         self.parser.add_argument(
             "--force",
             action="store_true",
@@ -282,12 +275,6 @@ def run(self, args, **kwargs):
         if not is_structured_output:
             self._get_content_counts_for_pack(args, **kwargs)
 
-        if args.python3:
-            warnings.warn(
-                "DEPRECATION WARNING: --python3 flag is ignored and will be removed "
-                "in v3.5.0 as StackStorm now runs with python3 only"
-            )
-
         return self.manager.install(
             args.packs,
             force=args.force,