Dario Conca (53) scored the only goal of the derby fixture to send Marcello Lippi's men 14 points clear of second-placed Shandong Luneng with eight games remaining.
Beijing Guoan are third after strolling to a 4-0 victory over Dalian Aerbin.
Joffre Guerron (22) and Jiayi Shao (86) notched in either half with Xizhe Zhang adding a brace of penalties (36 and 73).
Elsewhere, Jiangsu Shuntian climbed to 11th with a 2-1 win against Changchun Yatai.
Aleksandar Jevtic (13) and Xi Wu (63) got the goals Jiangsu needed to render Anzur Ismailov's 90th-minute strike a mere consolation.