Pérez de Cuéllar ya shiga Ma'aikatar Harkokin Waje a 1940 da kuma ma'aikatar diflomasiyya a 1944, daga bisani ya zama Sakatare a ofishin jakadancin Peru a Faransa, inda ya sadu kuma ya auri matarsa ta farko, Yvette Roberts (ya mutu Lisbon, 2013).
Yvette Roberts ta yi aure