Mbappe put PSG ahead after 11 minutes at Parc des Princes, with Carlos Soler heading in a second soon after half-time.
Achraf Hakimi slotted home a third just before the hour, with substitutes Renato Sanches and Hugo Ekitike both also on the scoresheet during the closing stages.
In Sunday's late match, Marseille moved up to fourth place, a point behind Rennes, after a dramatic 3-2 victory away at Monaco which saw Sead Kolasinac head home the winner deep into stoppage time.
Alexis Sanchez's fine free-kick gave the visitors the lead, but Wissam Ben Yedder equalised from the penalty spot at the end of the first half.
Kevin Volland then put Monaco in front with 18 minutes left, but Jordan Veretout levelled things up before former Arsenal defender Kolasinac glanced in Dimitri Payet's free-kick with just seconds to go.
A late goal from Habib Diallo earned strugglers Strasbourg a 1-1 draw against Lorient, who drop to fifth after seeing their winless run stretch to five matches having previously won six in succession, while bottom club Angers lost 1-0 at 10-man Lille.
AC Milan needed an injury-time own goal from Nikola Milenkovic to beat Fiorentina 2-1 at San Siro, which saw them close back to within eight points of leaders Napoli.
Rafael Leao had given the second-placed Rossoneri a flying start inside the opening two minutes, but Fiorentina were level before the break through a deflected effort from Antonin Barak.
Just when it seemed both teams would have to settle for a point, Fiorentina defender Milenkovic bundled a cross from Brahim Diaz into his own net to hand Milan victory.
In Sunday's evening match, Moise Kean scored twice to help Juventus beat Lazio 3-0 as Massimiliano Allegri's in-form side moved up to third with their sixth successive league win without conceding a goal.
Nemanja Matic's last-minute goal grabbed Roma a 1-1 draw against Torino at the Stadio Olimpico - where Giallorossi boss Jose Mourinho had been shown a late red card for arguing with officials.
Edin Dzeko scored twice as Inter Milan came from behind to win 3-2 at Atalanta while a brace from M'Bala Nzola gave Spezia a 2-1 win at bottom club Hellas Verona, who suffered a 10th consecutive Serie A defeat.
Vincenzo Grifo grabbed a hat-trick within the first 20 minutes as Freiburg beat 10-man Union Berlin 4-1 in an incident-packed clash at the Europa-Park Stadion to move second in the Bundesliga, four points behind Bayern Munich.
Grifo opened the scoring from the penalty spot after four minutes following a VAR review for handball - and the Italian forward soon doubled the lead.
Union defender Robin Knoche then saw his penalty hit the post before his team-mate Diogo Leite was shown a red card in the 19th minute after bringing down Freiburg forward Ritsu Doan as he raced in on goal, with Grifo slotting in the resulting spot-kick.
Michael Gregoritsch added a fourth for the home side just before the break, and Union substitute Sven Michel netted a late consolation for the visitors - who drop to fifth - from another penalty.
Elsewhere, Eintracht Frankfurt came from behind to draw 1-1 at Mainz and sit fourth.