The 1975 U.S.

Pro Indoor was a men's WCT tennis tournament played on indoor carpet courts at the Spectrum in Philadelphia, Pennsylvania in the United States.

It was the eighth edition of the tournament and was held from January 20 through January 26, 1975.

Seventh-seeded Marty Riessen won the singles title.

[3] Marty Riessen defeated Vitas Gerulaitis 7–6(7–1), 5–7, 6–2, 6–7(0–7), 6–3 [1] Brian Gottfried / Raúl Ramírez defeated Dick Stockton / Erik van Dillen 3–6, 6–3, 7–6(7–4) [2]