كتب : وكالات
The Argentinean in-form frontman opened the scoring after 22 minutes when he fired home from close range after a headed pass from Thiago Motta.
Bologna frontman Marcelo Zalayeta equalized just one minute later, superbly ghosting behind two defenders to control a long ball inside the area and slot home.
Mario Balotelli restored Inter's advantage three minutes before the break after heading in a corner and Esteban Cambiasso made sure of the victory on 72 minutes after being set up by Milito.
The Nerazzurri's right-back Maicon was sent off in stoppage time for dissent.
Defending champions Inter, who eye a fifth consecutive league title, extended their lead at the top to eight points.
Second-placed Juventus can cut the deficit back down to five if they beat Udinese on Sunday.
The match's highlights