diff --git a/airflow/api/common/mark_tasks.py b/airflow/api/common/mark_tasks.py
index 22cde7febf..d11f490247 100644
--- a/airflow/api/common/mark_tasks.py
+++ b/airflow/api/common/mark_tasks.py
@@ -468,7 +468,20 @@ def set_dag_run_state_to_failed(
         task.dag = dag
         tasks.append(task)
 
-    return set_state(tasks=tasks, run_id=run_id, state=State.FAILED, commit=commit, session=session)
+    # Mark non-finished tasks as SKIPPED.
+    tis = session.query(TaskInstance).filter(
+        TaskInstance.dag_id == dag.dag_id,
+        TaskInstance.run_id == run_id,
+        TaskInstance.state.not_in(State.finished),
+        TaskInstance.state.not_in(State.running),
+    )
+
+    tis = [ti for ti in tis]
+    if commit:
+        for ti in tis:
+            ti.set_state(State.SKIPPED)
+
+    return tis + set_state(tasks=tasks, run_id=run_id, state=State.FAILED, commit=commit, session=session)
 
 
 def __set_dag_run_state_to_running_or_queued(
diff --git a/airflow/www/views.py b/airflow/www/views.py
index 41740d9e64..f3113a251c 100644
--- a/airflow/www/views.py
+++ b/airflow/www/views.py
@@ -2119,7 +2119,7 @@ def _mark_dagrun_state_as_failed(self, dag_id, dag_run_id, confirmed, origin):
 
             response = self.render_template(
                 'airflow/confirm.html',
-                message="Here's the list of task instances you are about to mark as failed",
+                message="Here's the list of task instances you are about to mark as failed or skipped",
                 details=details,
             )
 
diff --git a/tests/api/common/test_mark_tasks.py b/tests/api/common/test_mark_tasks.py
index 7e461dc4e3..3a3bcfc621 100644
--- a/tests/api/common/test_mark_tasks.py
+++ b/tests/api/common/test_mark_tasks.py
@@ -450,6 +450,20 @@ def compare(x, y):
 
         return len([s for s in states if compare(s, state)])
 
+    def _get_num_tasks_with_non_completed_state(self):
+        """
+        Return the non completed tasks.
+        :return: number of tasks in non completed state (SUCCESS, FAILED, SKIPPED, UPSTREAM_FAILED)
+        """
+        expected = len(self.INITIAL_TASK_STATES.values()) - self._get_num_tasks_with_starting_state(
+            State.SUCCESS, inclusion=True
+        )
+        expected = expected - self._get_num_tasks_with_starting_state(State.FAILED, inclusion=True)
+        expected = expected - self._get_num_tasks_with_starting_state(State.SKIPPED, inclusion=True)
+        expected = expected - self._get_num_tasks_with_starting_state(State.UPSTREAM_FAILED, inclusion=True)
+
+        return expected
+
     def _set_default_task_instance_states(self, dr):
         for task_id, state in self.INITIAL_TASK_STATES.items():
             dr.get_task_instance(task_id).set_state(state)
@@ -514,8 +528,8 @@ def test_set_running_dag_run_to_failed(self):
         self._set_default_task_instance_states(dr)
 
         altered = set_dag_run_state_to_failed(dag=self.dag1, run_id=dr.run_id, commit=True)
-        # Only running task should be altered.
-        expected = self._get_num_tasks_with_starting_state(State.RUNNING, inclusion=True)
+        # Only non-completed tasks should be altered.
+        expected = self._get_num_tasks_with_non_completed_state()
         assert len(altered) == expected
         self._verify_dag_run_state(self.dag1, date, State.FAILED)
         assert dr.get_task_instance('run_after_loop').state == State.FAILED
@@ -561,8 +575,8 @@ def test_set_success_dag_run_to_failed(self):
         self._set_default_task_instance_states(dr)
 
         altered = set_dag_run_state_to_failed(dag=self.dag1, run_id=dr.run_id, commit=True)
-        # Only running task should be altered.
-        expected = self._get_num_tasks_with_starting_state(State.RUNNING, inclusion=True)
+        # Only non-completed tasks should be altered.
+        expected = self._get_num_tasks_with_non_completed_state()
         assert len(altered) == expected
         self._verify_dag_run_state(self.dag1, date, State.FAILED)
         assert dr.get_task_instance('run_after_loop').state == State.FAILED
@@ -609,8 +623,8 @@ def test_set_failed_dag_run_to_failed(self):
 
         altered = set_dag_run_state_to_failed(dag=self.dag1, run_id=dr.run_id, commit=True)
 
-        # Only running task should be altered.
-        expected = self._get_num_tasks_with_starting_state(State.RUNNING, inclusion=True)
+        # Only non-completed tasks should be altered.
+        expected = self._get_num_tasks_with_non_completed_state()
         assert len(altered) == expected
         self._verify_dag_run_state(self.dag1, date, State.FAILED)
         assert dr.get_task_instance('run_after_loop').state == State.FAILED
@@ -655,8 +669,8 @@ def test_set_state_without_commit(self):
 
         will_be_altered = set_dag_run_state_to_failed(dag=self.dag1, run_id=dr.run_id, commit=False)
 
-        # Only the running task should be altered.
-        expected = self._get_num_tasks_with_starting_state(State.RUNNING, inclusion=True)
+        # Only the non-completed tasks should be altered.
+        expected = self._get_num_tasks_with_non_completed_state()
         assert len(will_be_altered) == expected
         self._verify_dag_run_state(self.dag1, date, State.RUNNING)
         self._verify_task_instance_states_remain_default(dr)