On July 30, 1996, he was traded to the San Francisco Giants along with Tim Scott for Mark Leiter. Rueter blossomed into one of the Giants' most dependable starters. The following season, Rueter pitched in his first full season and to great success, going 13-6 with a 3.45 ERA in 32 starts with a career high 115 K's. In 1998, despite achieving a career high 16 victories, Rueter's ERA rose from the previous season, finishing with a 4.36 in 187+ innings.