Second-half goals from Mirko Vucinic and Claudio Marchisio earned the Bianconeri all three points to extend their advantage at the top of the table over Napoli and AC Milan, who play Atalanta and Pescara respectively on Sunday.
Bologna had their moments in the first half but were unable to build on a win over Inter Milan from last weekend.
Gianluigi Buffon showed great alertness and precision in the seventh minute, first to race off his line and then to prevent Alberto Gilardino from passing him with his right foot.
Juve responded with Sebastian Giovinco denied by Gianluca Curci and Arturo Vidal shooting over.
Gilardino thought he had opened the scoring in the 52nd minute with a bullet header which left Buffon no chance, but the linesman's flag had already been raised to cut short the home side's celebrations.
Two minutes later, Curci made a fine save to deny Giovinco as Juve appeared to move up a gear.
And in the 62nd minute, they took the lead when Marchisio played the ball to the feet of Vucinic on the edge of the area and he turned to shoot low past Curci.
Vucinic then returned the favour in the 74th minute to set up Marchisio, who picked his spot in the bottom right-hand corner to see off Bologna's challenge and give Juve a comfortable lead at the top of the standings.