He first played for the German national team in an exhibition game against France on 27 August 2016. A couple of days later, he scored the game-winning goal in the last game of the qualification tournament for the 2018 Winter Olympics against host Latvia, which gave Germany a place in Pyeongchang. Kühnhackl was born and raised in Landshut, Bavaria, and first began to play hockey at age two. His father, Erich, played in the top German leagues from 1968 until 1989 and appeared in five Winter Olympics for West Germany. He was named Germany's ice hockey player of the 20th century in 2000. Kühnhackl has been a lifelong fan of the Pittsburgh Penguins, the team that drafted him. He got his start in hockey at age five, following in his family's footsteps—his brother, sister and dad all played hockey in Germany.