diff --git a/changelog/6986.bugfix.md b/changelog/6986.bugfix.md
new file mode 100644
index 000000000000..dbea6c7417ba
--- /dev/null
+++ b/changelog/6986.bugfix.md
@@ -0,0 +1 @@
+- Updated Slack Connector for new Slack Events API
diff --git a/rasa/core/channels/slack.py b/rasa/core/channels/slack.py
index a04cc44f52bc..ff413cb1aa41 100644
--- a/rasa/core/channels/slack.py
+++ b/rasa/core/channels/slack.py
@@ -211,7 +211,7 @@ def _is_user_message(slack_event: Dict) -> bool:
         )
 
     @staticmethod
-    def _sanitize_user_message(text, uids_to_remove) -> Text:
+    def _sanitize_user_message(text: Text, uids_to_remove: List[Text]) -> Text:
         """Remove superfluous/wrong/problematic tokens from a message.
 
         Probably a good starting point for pre-formatting of user-provided text
@@ -367,10 +367,19 @@ def get_metadata(self, request: Request) -> Dict[Text, Any]:
             event = slack_event.get("event", {})
             thread_id = event.get("thread_ts", event.get("ts"))
 
+            users = []
+            if "authed_users" in slack_event:
+                users = slack_event.get("authed_users")
+            elif (
+                "authorizations" in slack_event
+                and len(slack_event.get("authorizations")) > 0
+            ):
+                users.append(slack_event.get("authorizations")[0].get("user_id"))
+
             return {
                 "out_channel": event.get("channel"),
                 "thread_id": thread_id,
-                "users": slack_event.get("authed_users"),
+                "users": users,
             }
 
         if content_type == "application/x-www-form-urlencoded":
@@ -379,10 +388,15 @@ def get_metadata(self, request: Request) -> Dict[Text, Any]:
             payload = json.loads(output["payload"][0])
             message = payload.get("message", {})
             thread_id = message.get("thread_ts", message.get("ts"))
+
+            users = []
+            if payload.get("user", {}).get("id"):
+                users.append(payload.get("user", {}).get("id"))
+
             return {
                 "out_channel": payload.get("channel", {}).get("id"),
                 "thread_id": thread_id,
-                "users": payload.get("user", {}).get("id"),
+                "users": users,
             }
 
         return {}
diff --git a/tests/core/test_channels.py b/tests/core/test_channels.py
index bf374ba9f1e8..901d38ee83ab 100644
--- a/tests/core/test_channels.py
+++ b/tests/core/test_channels.py
@@ -587,7 +587,7 @@ def test_slack_form_metadata():
     r.headers = header
     metadata = input_channel.get_metadata(request=r)
     assert metadata["out_channel"] == channel
-    assert metadata["users"] == authed_user
+    assert metadata["users"][0] == authed_user
     assert metadata["thread_id"] == ts
 
 
@@ -631,7 +631,7 @@ def test_slack_metadata_missing_keys():
     r.json = direct_message_event
     r.headers = header
     metadata = input_channel.get_metadata(request=r)
-    assert metadata["users"] is None
+    assert metadata["users"] == []
     assert metadata["out_channel"] == channel
     assert metadata["thread_id"] == ts
 
@@ -675,7 +675,7 @@ def test_slack_form_metadata_missing_keys():
     r.form = form_event
     r.headers = header
     metadata = input_channel.get_metadata(request=r)
-    assert metadata["users"] is None
+    assert metadata["users"] == []
     assert metadata["out_channel"] == channel
     assert metadata["thread_id"] == ts