Throughout the 1960s and 1970s Irma Cordero played volleyball for the Peru national team, winning multiple championships and medals. In 1967 Cordero was part of the team that won silver at the Pan American Games in Winnipeg, only losing to the United States during the round-robin tournament. She won two further silver medals at the Pan American Games, with Peru finishing as runners-up in both 1971 and 1975. Cordero was also a two-time Olympian, first competing at the 1968 Mexico City Games, with Peru finishing fourth, before placing seventh at the 1976 Games in Montréal. Her best record came at the South American Championships, winning five golds (1967, 1971, 1973, 1975, 1977) and a silver (1969). Cordero helped to make volleyball popular in Peru with multiple tours with the national team across the country, in addition to coaching the national youth team.