The 1975 South Orange Open, also known as the Tennis Week Open, was a men's tennis tournament played on outdoor clay courts at the Orange Lawn Tennis Club in South Orange, New Jersey in the United States. It was classified as a Group B category tournament and was part of the 1975 Grand Prix circuit. It was the sixth edition of the tournament on the Grand Prix circuit and was held from August 18 through August 24, 1975. Second-seeded Ilie Năstase won the singles title. The final was delayed for two days due to rain.[3][4]