diff --git a/django/db/backends/oracle/operations.py b/django/db/backends/oracle/operations.py
index 964edc4549..ae6bd432fb 100644
--- a/django/db/backends/oracle/operations.py
+++ b/django/db/backends/oracle/operations.py
@@ -258,16 +258,14 @@ END;
         columns = []
         for param in returning_params:
             value = param.get_value()
-            if value is None or value == []:
-                # cx_Oracle < 6.3 returns None, >= 6.3 returns empty list.
+            if value == []:
                 raise DatabaseError(
                     'The database did not return a new row id. Probably '
                     '"ORA-1403: no data found" was raised internally but was '
                     'hidden by the Oracle OCI library (see '
                     'https://code.djangoproject.com/ticket/28859).'
                 )
-            # cx_Oracle < 7 returns value, >= 7 returns list with single value.
-            columns.append(value[0] if isinstance(value, list) else value)
+            columns.append(value[0])
         return tuple(columns)
 
     def field_cast_sql(self, db_type, internal_type):
diff --git a/docs/ref/databases.txt b/docs/ref/databases.txt
index 04f420984c..67d6d21eb6 100644
--- a/docs/ref/databases.txt
+++ b/docs/ref/databases.txt
@@ -842,7 +842,7 @@ To enable the JSON1 extension you can follow the instruction on
 Oracle notes
 ============
 
-Django supports `Oracle Database Server`_ versions 19c and higher. Version 6.0
+Django supports `Oracle Database Server`_ versions 19c and higher. Version 7.0
 or higher of the `cx_Oracle`_ Python driver is required.
 
 .. _`Oracle Database Server`: https://www.oracle.com/
diff --git a/docs/releases/4.0.txt b/docs/releases/4.0.txt
index 185159d9ad..b7b0eec1b2 100644
--- a/docs/releases/4.0.txt
+++ b/docs/releases/4.0.txt
@@ -251,7 +251,7 @@ officially supports Oracle 19c.
 Miscellaneous
 -------------
 
-* ...
+* Support for ``cx_Oracle`` < 7.0 is removed.
 
 .. _deprecated-features-4.0:
 
diff --git a/tests/requirements/oracle.txt b/tests/requirements/oracle.txt
index 763baa8579..5027358943 100644
--- a/tests/requirements/oracle.txt
+++ b/tests/requirements/oracle.txt
@@ -1 +1 @@
-cx_oracle >= 6.0
+cx_oracle >= 7.0