The man was shot in the Galliagh Park area of the city at 11.40pm last night (Monday, July 3).
He was taken to hospital for treatment to his injuries which are not believed to be life threatening.
A PSNI spokesperson said: “Police would condemn this brutal attack and would ask anyone with information to contact 101 quoting reference 1498 of 3/7/17 or if they wish to remain anonymous Crimestoppers on 0800 555 111.”