Ernest Ahwireng Obeng (born 8 April 1956) is a retired Ghanaian sprinter who specialized in the 100 metres. His personal best time was 10.21 seconds, achieved in August 1980 in Budapest. Ghana boycotted the Olympic Games that year.
He won the gold medals at the 1979 African Championships and 1982 African Championships, and won a bronze medal at the 1981 Universiade. Obeng also competed at the 1983 World Championships, and won the British AAA Championships in 1985.
Obeng also represented Africa in the 100 metres at the 1981 IAAF World Cup, finishing second behind Allan Wells of Europe.
He is now in charge of television operations for the International Association of Athletics Federations, working from their offices in Monaco.