Moukoko made his debut for Stefan Kuntz's side in their UEFA European Championship qualifying game against San Marino on 2 September 2021, as they begin the defence of their title which they won this summer.
Aged 16 years and 286 days, Moukoko surpasses Bayer Leverkusen midfield Wirtz who, aged 17 years and 159 days, only became the youngest U21 international for Germany in October of 2020.
The Leverkusen midfielder had beaten the record of Schalke and Wolfsburg winger Draxler - now of Paris Saint-Germain and a fully fledged Germany international - by 164 days.
For Moukoko, it's another record to add to his host of career milestones already achieved despite his tender years. The Cameroon-born forward is already the youngest player and scorer in Bundesliga history having made his debut for Dortmund in November 2020 against Hertha Berlin, just one day after his 16th birthday.
Just 27 days later, in December, Moukoko became the league's youngest scorer when he came on to notch the first of his now three top-flight goals against Union Berlin.
Top 10 youngest Germany U21 debutants
1) Youssoufa Moukoko (16 years and 286 days)
2) Florian Wirtz (17 years, 159 days)
3) Julian Draxler (17 years, 323 days)
4) Richard Sukuta-Pasu (18 years, 56 days)
5) Mario Götze (18 years, 92 days)
6) Ashkan Degajah (18 years, 95 days)
7) Mats Hummels (18 years, 101 days)
8) Olaf Thon (18 years, 133 days)
9) Christian Wörns (18 years, 152 days)
10) Marko Marin (18 years, 161 days)