The former World Cup winner passed the previous record of 647 appearances held by AC Milan great Paolo Maldini.
Buffon, who spent last season at French club Paris Saint-Germain before rejoining Juve this term, signed a one-year contract extension earlier this week.
It is the eighth Serie A appearance this campaign for Buffon, with Polish international Wojciech Szczesny usually the defending champions’ number one.
The record comes 25 years after Buffon made his Serie A debut for Parma and 19 years after he first signed for Juventus.
“The truth is that I’m still playing because I feel good, I’m competitive and also because I know I can get better,” Buffon said during a live interview on Instagram on Thursday.
“When you have room for improvement, you have that fire inside you that means you’re not satisfied with yourself.”
He also holds the record for most appearances with the Italy national team of 176, although he retired from international duty in 2018 after their failure to qualify for the World Cup in Russia.
Serie A leaders Juventus kicked off Saturday’s game four points clear of second-placed Lazio with nine matches remaining of the season.
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