Ezekiel Lavezzi, who had previously netted four league goals this season, struck twice in the first half and again after the break.
Edinson Cavani, with a double, and Maxwell completed the rout. PSG have 68 points with five games left, three ahead of second-placed Olympique Lyonnais who travel to Stade de Reims on Sunday.
Lille, who grabbed a consolation goal through Marko Basa in the 59th minute, finished with 10 men after Sebastien Corchia was sent off in the 72nd.
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Story by Ghana/Joy Sports/Gary Al-Smith