Goals either side of the break from Armando Izzo and Iago Falque consigned Atalanta to its second successive loss and left it seven points behind AC Milan, which currently occupies fourth place and the final Champions League qualifying berth.
Torino, which has European ambitions of its own, moved level on points with Atalanta and Lazio following another superb defensive display. It was its fifth successive match without conceding.
Torino broke the deadlock three minutes before halftime. A corner ricocheted around the box and, although Atalanta goalkeeper Etrit Berisha made a save, the ball came to Izzo and he finished it off from close range.
The home side doubled its tally less than a minute after the interval as Soualiho Meite put in a cross from the left for Iago Falque to drill into the bottom right corner.