Goals from Javier Pastore and Zlatan Ibrahimovic gave Paris Saint-Germain nine points from five games.
"We are starting to show how strong we are but we know we can do even better," PSG captain Christophe Jallet told the beIN SPORT television channel.
Ibrahimovic, the league's top scorer with five goals, shone again, two weeks after his double gave unbeaten PSG their first win of the season against Lille.
The Sweden striker almost put his team in front at the Parc des Princes but he was denied by Toulouse keeper Ali Ahamada.
PSG eventually went ahead in the 38th minute when Pastore, who was superbly set up by Marco Verratti, lobbed Ahamada.
Argentine Pastore also played a part in the second goal by Ibrahimovic in the 69th minute as PSG warmed up in style for Tuesday's Champions League game against Dynamo Kiev.
Montpellier, who make their Champions League debut against Arsenal on Tuesday, occupy 14th place in Ligue 1 after losing at Stade de Reims.
The visitors wasted two good chances to go in front before Diego put Stade de Reims ahead following a sweeping move in the 38th minute.
Montpellier equalised 10 minutes into the second half when Remy Cabella netted from close range after a fine one-two with Younes Belhanda.
The home team edged 2-1 ahead when Christopher Glombard dispossessed Henri Bedimo and beat keeper Geoffrey Jourdren.
Substitute Gaaetan Courtet sealed victory in the 86th minute as Stade de Reims rose to eighth spot.
