Originally part of the Chinese youth team he would make the transition to the senior team when he made his debut against Indonesia on April 20, 1992 in an Asian Cup qualifier that China won 2-0. He would immediately become an integral member of the Chinese team and would play in the 1992 AFC Asian Cup where he aided China to a third-place finish as well as also scoring his first goal against Qatar during the tournament. In the 1994 Asian Games he would continue to aid China to this time a runners-up position, however when it came to the 1996 AFC Asian Cup he was unable to help China improve upon their previous results and China were knocked out during the quarter-finals. Unable to help China qualify for the 1998 FIFA World Cup Peng Weiguo would play his last international game in the final game of qualifying.