Sorin Cătălin Frunză (born 29 March 1978) is a Romanian professional footballer who plays as a left midfielder for Liga IV side Avântul Valea Mărului.

On 30 March 2008, Frunză alongside team-mates Silviu Bălace and Daniel Sabou were accused by Adrian Porumboiu of fixing a match against Steaua București.

In the 2004–05 summer, he was loaned to U Craiova, but he stayed there only half of season, after that he returned at Vaslui, where he succeeded promotion for the first time in history club, in Liga I.

Frunză quickly established himself as a key member in Dan Petrescu's team and helped the side to its first championship title in history in the 2008–09 season.

Frunză was a starter in all six Champions League matches for Unirea as the team finished third with eight points, behind FC Sevilla and Vfb Stuttgart, but ahead of Rangers.

On 6 March 2010, Frunză was named best player of Unirea in the derby against Steaua Bucharest after scoring once and providing an assist for team-mate Marius Onofras.