The 1975 Dutch Open – Singles was an event of the 1975 Dutch Open tennis tournament and was played on outdoor clay courts at 't Melkhuisje in Hilversum in the Netherlands from 20 July until 27 July 1975. The draw comprised 32 players. Guillermo Vilas was the defending Dutch Open champion and retained his singles title by defeating Željko Franulović in the final, 6–4, 6–7, 6–2, 6–3.[1] [2]