Utaka moved to Croatia as a 16-year-old to play in Dinamo Zagreb after trying his luck at Ismaily where his older brother John was a cult figure and in the United Arab Emirates. In 2003 he moved to Belgium from Dinamo and signed for K. Patro Eisden Maasmechelen of the 2nd division. KVC Westerlo moved to sign him the following season, and in his first season in the top flight and the transfer was worth 250 000 euro.
He joined Royal Antwerp FC in January 2007 where he became a first team regular, and he helped Antwerp qualify for the playoffs, finishing second. He also emerged top scorer with 22 goals and capped hs glorious season, winning the Best Striker's Award. He also put more gloss on his breath-taking performance that season, claiming the Most Valuable Player's award over eight times, making him one of the most feared strikers in Belgium. On 30 August 2008, it was announced that Utaka would join Danish club OB. for an undisclosed fee.
Utaka joined Danish side OB in 2008. In his first season he finished joint fourth place on the scorers list, while he led all scorers in his second season. He finished with 18 goals in 33 matches, the first time in five years an OB player was top scorer in the league (last was Steffen Højer in 2004–05 with 20 goals). His Danish team- OB included also two former Manchester United players- Roy Carroll and Eric Djemba-Djemba and another former French international player- Bernard Mendy.
In January 2012, Utaka moved to Chinese Super League club Dalian Aerbin he scored 20 goals in 28 games in his first season playing alongside former Barcelona players -Fabio Rochemback and Seydou Keita, as well as former Australian International player- Mille Sterjovski and former PSG player- Guillaume Hoarau. He also scored 11 consecutive fixtures to establish a new C-league record.He transferred to Beijing Guoan on 9 July 2013 in 2M Euro transfer. That made him the most expensive international signing in the history of the club. He also played with former Sevilla and Mali captain- Freddy Kanoute.
On 21 September 2009, national coach Shaibu Amodu selected Peter for the Nigerian national football team. Utaka made his debut for Nigeria months later in a 5–2 home win over Congo DR on 3 March 2010, despite only getting his call up late after the NFF called his mother looking for him. He scored the first goal and assisted on the second. He scored twice against in a Nations Cup qualifier against Ethiopia. His first goal was the fastest goal in the qualifications-29secs.