Oruma was part of the Nigeria under-17 team which won the 1993 FIFA U-17 World Championships, captaining his side and becoming the tournament's top goalscorer with 6 goals. He played 19 times international matches over 11 years for Nigeria and was part of the team that participated in the 1998 FIFA World Cup, where he scored in the only appearance he made in the tournament against Paraguay. He also was part of the squad that won the Olympic gold medal in 1996, a year after he debuted for Nigeria, and also a member of the Nigerian squad at the 2002 and 2006 Africa Cup of Nations, finishing both competitions at third place.