Born in Enugu, Nigeria, 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.
Royal Antwerpen
Utaka 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.
Odense Boldklub
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. In the 2009–10 Danish Superliga he finished with 18 goals in 33 matches, the first time in five years an OB player was top scorer in the league. Utaka stayed in OB for three and a half season winning three silver medals in his first three seasons in the Danish Superliga. He also represented the club in both UEFA Europa League and the 2011-2012 Champions League qualifying phase scoring a total of nine goals in 22 European matches for the club.
In January 2012, Utaka moved to Chinese Super League club Dalian Aerbin. He scored 20 goals in 28 games in his first season. He also scored 11 consecutive fixtures to establish a new C-league record.
He transferred to Beijing Guoan on 9 July 2013 in a €2 million transfer which made him the most expensive international signing in the history of the club. Utaka made 15 goals in 36 appearances in all competitions for the club, before he was loaned to Shanghai Shenxin during summer transfers in 2014, managing to score only four times in thirteen appearances in all competition for the Shanghai outfit.
In January 2015, Utaka transferred to J1 League-club Shimizu S-Pulse. The club faced a difficult season that year as they were battling relegation. At the end of the season, Utaka scored nine goals in 29 appearances, and the club ended up being seventeenth-placed, thus relegated into the J2 League.
The next year he was loaned to J1 League defending champions Sanfrecce Hiroshima. He scored his first goal for the club in the Japanese Super Cup final, in a 3–1 win against Gamba Osaka. Utaka bagged his first goal in the J1 League on 12 March, scoring a 67th-minute penalty against Shonan Bellmare in a 2–2 draw at home. He scored his next in a 1–5 away win against Omiya Ardija, scoring the opening in the 22nd minute.
After being bought by Sanfrecce Hiroshima, he was imeadeately loaned to FC Tokyo in March 2017. He scored four goals in his first three matches for the J1 League-club even though he started all of the matches on the bench. He represented the club 33 times and scored 10 goals before he returned to Sanfrecce Hiroshima and his contract expired.
In February 2018 free agent Utaka trialled with Danish side Vejle Boldklub in Turkey, where the club was on a training camp. Utakas agent Lucas Chang Jin is co-owner of Vejle Boldklub who at that time was number one in the Danish second tier. On 14 February 2018, the club announced thar Utaka had signed a contract until the summer of 2018.
International career
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.