Klaassen
Klaasen is Dutch patronymic surname. Notable people with this name include:
- Arno Klaassen, Dutch bobsledder
- Davy Klaassen, Dutch footballer
- Jozef Klaassen, Dutch rower
- , Dutch economist
- Mihkel Klaassen, Estonian Supreme Court judge
- Nel Klaassen, Dutch sculptor
- René Klaassen, Dutch field hockey player
- Fred Klaassen, Dutch cricketer
- Ryan Klaassen, lead plaintiff in the 2021 vaccine law case Klaassen v. [Indiana University]
- Jan Klaassens, Dutch footballer