Calvin Peete, who got his only other PGA Tour victory here in 1979, shot three-under-par 69 today to win the Greater Milwaukee Open.

He won by two strokes, shooting 274 for four rounds over Tuckaway Country Club's hilly course, and won $45,000. Second was Victor Regalado, who shot 71 today.

Peete, a seven-year veteran, clinched today's victory with a birdie on the 17th hole. Terry Diehl, coleader at the time, bogeyed that 220-yard par-3 for a two-shot swing. Diehl shot 71 and was third at 277.

Dick Zokol, the Canadian rookie who shared the lead after each of the first three rounds, dropped out of contention with a bogey at 15, a double bogey at 16 and a bogey at 17. Zokol, who wore a radio headset to relax himself during the tournament, shot 75, but still had his best U.S. finish by far: a tie for fifth at 279 with Morris Hatalsky and Larry Ziegler. It was worth $9,125, more than three times what Zokol previously had won in 20 tour starts.

Wayne Levi, the 54-hole coleader with Zokol, was tied for the lead after birdies at Nos. 6 and 7. But three straight bogeys, starting at No. 8, led him to a 76--280.