At age 18 years, 140 days, the Monaco striker made history with a 69th-minute goal on Tuesday, converting from a close-range Joao Moutinho pass.
The goal also put an end to Juventus' 689-minute shutout streak – the second longest in Champions League history.
The teenager's strike was only a consolation for Monaco, with the goal making it 2-1 Juve on the night and 4-1 on aggregate. The Old Lady advanced to the final in Cardiff with a 4-1 win over the two legs.
Mbappe has now scored in five of his first six Champions League knockout matches, with the semi-final first leg in Monaco the only match in which he's failed to find the back of the net.