Monaco stunned both Manchester City and Borussia Dortmund to reach the last four with some vibrant attacking play.
Buffon, 39, said: “They have youth and the insouciance that comes with it.
“But I think over the two matches, 180 minutes, experience will play into our hands.”
Monaco’s 18-year-old forward Kylian Mbappe has caught the eye of top European clubs with a run of five goals in four knockout matches against City and Dortmund, and Leonardo Jardim’s free-scoring team have scored 95 goals in 34 league games so far.
They are on course for a first French league title since 2000, and will match their achievement of reaching the 2004 Champions League final if they are victorious over two legs against Juve.
Juventus themselves are nine points clear at the top of Serie A – which they have won for the past five years – and are hoping for a second final appearance in three years.
“I remember when I was young having that feeling of being indestructible,” Buffon said.
“Monaco are a daring team – they like to attack and they do it very well.
“Their coach has an attacking philosophy and their players have scored an avalanche of goals this season.”
Monaco hope midfielder Tiemoue Bakayoko will be available to play – possibly in a protective mask – despite breaking his nose.
Juventus are almost at full strength, with suspended midfielder Sami Khedira the only definite absentee.
Coach Massimiliano Allegri said his side will need “two great performances” to reach the final, while Monaco boss Jardim said Juve’s “winning culture” made them tough opposition.