The 1970 Cincinnati Open (also known as the Western Tennis Championships for sponsorship reasons) was a tennis tournament played on outdoor clay courts at the Coney Island in Cincinnati, Ohio in the United States that was part of the 1970 Pepsi-Cola Grand Prix. The tournament was held from July 20 through July 26, 1970. Ken Rosewall won the singles title.
Ken Rosewall defeated Cliff Richey 7–9, 9–7, 8–6
Ilie Năstase / Ion Ţiriac defeated Bob Hewitt / Frew McMillan 6–3, 6–4