Soto obtained 75 international caps for the Peru national team, scoring three goals. He made his debut on November 25, 1992 in a 1-1 draw against Ecuador, and played his last international match at age 33 in a World Cup qualifying defeat against Chile on September 9, 2003. Soto's international career included the Copa América tournaments of 1993, 1995, 1999, and 2001.