During most of his working life, Petrović worked at the Doboj Police Station and he was head of the Civil Protection Department of the Doboj Municipality until his appointment as Mayor of the Municipality in 2002.
Under det meste af sit arbejdsliv har Petrovic arbejdet på Doboj politistation, og han var leder af civilforsvaret i Doboj Kommune indtil han blev udnævnt til borgmester i kommunen i 2002.