Former Post reporter Joseph H. Nicholson Jr., the nation’s first openly gay big-city newspaper reporter, died early Wednesday at the age of 71.

He joined The Post in 1971 and came out to his colleagues in 1980, following a shooting at a West Street gay bar, where two men were killed and six wounded by a deranged man.

Nicholson, who was fluent in Spanish, interviewed Cuban dictator Fidel Castro in 1973 and broke a story about secret talks between Havana and Washington to solve a rash of airplane hijackers.

In 1993, during the height of debate on gays in the military, he wrote a first-person account on his experiences as closeted Navy officer when he served in the mid-1960s.

He is survived by his husband, Sherwin T. Nicholson, and sister, Katherine Nicholson Pendergast.

The wake will take place Friday from 4 to 8 p.m. at Redden’s Funeral Home, 325 W. 14th St.

The funeral service will take place Saturday, Oct. 11, at 9:30 a.m. at The Church of the Holy Apostles, 269 Ninth Avenue at 28th Street, the church where Joe and Sherwin were married last year.