Mulenga got his call-up to the national team in 1980 and was the reserve keeper at Moscow Olympic Games. His international debut came in December 1980 in a 1–1 draw with Kenya during that country’s independence celebrations in Kisumu. He was in goal during Zambia’s 2-0 win over Morocco in 1981, which saw the country through to CAN 1982 in Libya. He played a key role at the CAN as Zambia went up to the semi-finals only to lose a tough match against the hosts 2–1, with Mulenga being stretchered off in the 25th minute with a cut above the eye, after which the Libyans managed to get their two goals.