Former world super bantamweight and featherweight champion Wilfredo Gomez of Puerto Rico won his third world title yesterday, defeating World Boxing Association junior lightweight champion Rocky Lockridge with a 15-round split decision in San Juan, Puerto Rico.

Gomez, 28, raised his record to 42-2-1 with 40 knockouts, while Lockridge, 26, of Tacoma, Wash., dropped to 36-4 with 30 knockouts. Gomez, 129 pounds, became the first boxer to win three world titles in the lower weight categories. Lockridge, 128 1/2, was making his third defense of the crown he won in February 1984 when he defeated Roger Mayweather.

About 9,000 fans attended the match at the Roberto Clemente Coliseum . . .

In Reno tonight, Larry Holmes will fight for the third time in six months, defending his International Boxing Federation heavyweight title in a scheduled 15-round bout against Carl (The Truth) Williams.

Holmes, closing in on Rocky Marciano's record of 49 bouts without a loss, wants two more fights in 1985. He is 47-0, with 33 knockouts. Williams is 16-0 with 12 knockouts.

The telecast (WRC-TV-4) starts at 9 p.m., with the main event expected to begin at about 9:50.

Holmes weighed in yesterday at 222 1/4 and Williams at 215.