Mbappe opened the scoring with a low shot through Strasbourg goalkeeper Matz Sels’ legs.
Further goals from Pablo Sarabia and Moise Kean extended PSG’s lead before half-time.
Dion Moise Sahi pulled one back for Strasbourg, but Leandro Paredes completed the scoring late on.
Lille, who won 2-0 at Metz on Friday, remain three points clear of second-placed PSG at the top of the table.
Mauricio Pochettino’s side host reigning European champions Bayern Munich in their Champions League quarter-final second leg on Tuesday, leading 3-2 from the first leg in Germany.
- Chelsea with an impressive win over Crystal Palace
- Liverpool scores late goal to win Aston villa
- Bellingham scores as Dortmund came from behind to win Stuttgart