The 1970 Washington Star International was a men's tennis tournament and was played on outdoor clay courts. It was the second edition of the tournament and was part of the 1970 Grand Prix circuit. It was held in Washington, D.C. from July 13 through July 19, 1970. Cliff Richey won the singles title and earned a $7,000 first prize.
Cliff Richey defeated Arthur Ashe 7–5, 6–2, 6–1 
Bob Hewitt / Frew McMillan defeated Ilie Năstase / Ion Țiriac 7–5, 6–0