The Italian top flight is one of the leagues trialling VAR this season.
Juve beat Genoa 4-2 on Saturday with both sides having penalties awarded following video consultation.
"They are overusing it and making mistakes. I don't like it this way, it's not good," keeper Buffon said.
"It's something which, if used sparingly, could give us excellent results and be a good thing for football.
"In this way, we won't know the real value of a referee. If everyone was a little calmer and more objective, and accepted mistakes, we would accept results with more humanity.
"Another thing is that in football, it's not a penalty every time there is contact. You can't stop the game every three minutes - it makes it like water polo."
Juve also conceded a penalty to Cagliari on the opening day using VAR, although Buffon saved it in a 3-0 win.
Coach Massimiliano Allegri is also unimpressed.
"Another thing is that the matches become very long and we don't know when they're going to finish," he said.
Gianluigi Buffon thinks Serie A referees are overusing the video assistant referee system after Juventus conceded a penalty using the method for the second game in a row.