Aebischer has represented Switzerland internationally on many occasions. His first international experience came in the 1997 World Junior Ice Hockey Championships, hosted by Switzerland. The Swiss finished in 7th place. Aebischer returned as Switzerland's starting goaltender the following year at the 1998 World Juniors and led the team past the quarterfinal round and to a bronze medal finish, defeating the heavily favoured Czech Republic in the bronze medal match. Aebischer has also appeared for Switzerland in five IIHF World Championships and two Winter Olympic Games.