Facing its stiffest challenge this season against the seven-time champions, PSG needed two own-goals from Lyon defenders Marcelo and Jeremy Morel. PSG now leads defending champion Monaco by three points.
PSG enjoyed most of the possession but its attacking "MCN" trident of Kylian Mbappe, Cavani and Neymar was not as flamboyant as in previous matches. Lyon defended well and prevented Neymar from making his mark while Cavani had only a few touches.
Lyon goalkeeper Anthony Lopes made several decisive saves and sent a penalty kick from Cavani onto the bar in the 79th minute. Moments before, Cavani and Neymar had been seen arguing about who should take the penalty.
A few minutes before that, Cavani had tried to take a free kick but Neymar's good friend and fellow Brazilian Dani Alves took the ball and gave it to the former Barcelona star. Cavani thrived last season as PSG's main striker, finishing as the French league's top scorer and bagging a remarkable 49 goals in 50 games across all competitions. Neymar's arrival from Barcelona for a world record 222 million euros ($262 million) has taken the spotlight away from him.
Cavani went back to the dressing room straight after the final whistle while his teammates celebrated on the pitch PSG was fortunate to open the scoring 15 minutes from time when Marcelo deflected a flick from Cavani into his own net. The hosts doubled their lead nine minutes later when Mbappe was set up by Neymar and forced Lopes into another good save, with the ball bouncing back onto Morel and into the net.
Lyon suffered toward the end but created several chances on the break as Nabil Fekir used his speed and fast dribbles to unsettle PSG's back four. The visitors' best chance came with 22 minutes left when newly hired Tanguy Ndombele fired a shot that crashed onto the bar.
Clinton Njie scored two goals in three minutes as Marseille won its first league match in a month, 2-0 at promoted Amiens on Sunday.
After conceding nine goals in back-to-back defeats against Monaco and Rennes, Marseille needed a good result on the road to calm its fans, who asked for coach Rudi Garcia's dismissal.
Njie, who picked up an injury during the warmup last weekend and could not play against Rennes, made a successful return. He started up front with Dimitri Payet and opened the scoring just after the interval from close range.
Three minutes later, he combined well with Florian Thauvin in the Amiens box and completed his brace with a clean finish.
Marseille moved to within eight points of PSG.
SUPER MARIO STRIKES
Mario Balotelli scored a late goal as Nice claimed a third consecutive win in all competitions with a 1-0 defeat of Rennes.
Balotelli was perfectly set up on the right side of the pitch by Alassane Plea's through ball 11 minutes from time. The former Manchester City striker beat the offside trap, rushed into the box and unleashed a powerful strike into the top right corner.
It was Nice's first away win in the league this season. Following a stuttering start to the season, Nice moved to eighth place in the standings, just four points behind third-place Saint-Etienne.
BETTER LATE THAN NEVER
Last-place Metz secured its first win this season and a first clean sheet since May by winning 1-0 at Angers.
Nolan Roux, the club's top scorer this season with two goals, slotted home the winner with a diving header.