diff --git a/src/managers/issue.py b/src/managers/issue.py
index 632d4e6..e37a6d7 100644
--- a/src/managers/issue.py
+++ b/src/managers/issue.py
@@ -24,7 +24,9 @@ def handle_tasklist(event: IssuesEvent):
     repository = event.repository
     issue = event.issue
     issue_body = issue.body
+    all_checked = []
     for checked, task in get_tasklist(issue_body):
+        all_checked.append(checked)
         if task_issue := get_issue(gh, repository, task):
             handle_issue_state(checked, task_issue)
 
@@ -47,3 +49,5 @@ def handle_tasklist(event: IssuesEvent):
             issue_body = issue_body.replace(task, issue_ref(created_issue))
     if issue_body != issue.body:
         issue.edit(body=issue_body)
+    if all_checked and all(all_checked):
+        issue.edit(state="closed")
diff --git a/tests/managers/test_issue.py b/tests/managers/test_issue.py
index ebd11f8..e5d138c 100644
--- a/tests/managers/test_issue.py
+++ b/tests/managers/test_issue.py
@@ -1,4 +1,4 @@
-from unittest.mock import Mock, patch
+from unittest.mock import Mock, call, patch
 
 import pytest
 
@@ -76,11 +76,33 @@ def test_handle_tasklist_with_repository_name_and_title(
 
 
 def test_handle_tasklist_with_issue_in_task_list(event, issue, repository):
-    issue.body = "- [x] #123"
+    issue.body = "- [ ] #123"
     repository.get_issue.return_value = issue
     with patch("src.managers.issue.handle_issue_state") as handle_issue_state:
         handle_tasklist(event)
-    handle_issue_state.assert_called_once_with(True, issue)
+    handle_issue_state.assert_called_once_with(False, issue)
     repository.get_issue.assert_called_once_with(123)
     repository.create_issue.assert_not_called()
     issue.edit.assert_not_called()
+
+
+def test_handle_tasklist_when_not_all_tasks_are_done(event, issue, repository):
+    issue.body = "- [x] #123\r\n- [ ] #321"
+    repository.get_issue.return_value = issue
+    with patch("src.managers.issue.handle_issue_state") as handle_issue_state:
+        handle_tasklist(event)
+    handle_issue_state.assert_has_calls([call(True, issue), call(False, issue)])
+    repository.get_issue.assert_has_calls([call(123), call(321)])
+    repository.create_issue.assert_not_called()
+    issue.edit.assert_not_called()
+
+
+def test_handle_tasklist_when_all_tasks_are_done(event, issue, repository):
+    issue.body = "- [x] #123\r\n- [x] #321"
+    repository.get_issue.return_value = issue
+    with patch("src.managers.issue.handle_issue_state") as handle_issue_state:
+        handle_tasklist(event)
+    handle_issue_state.assert_has_calls([call(True, issue), call(True, issue)])
+    repository.get_issue.assert_has_calls([call(123), call(321)])
+    repository.create_issue.assert_not_called()
+    issue.edit.assert_called_once_with(state="closed")