Koistinen
Koistinen is a Finnish surname. Notable people with the surname include:
- Al Koistinen, American former politician
- Hannu Koistinen, Finnish kantele maker
- Katri Helena Kalaoja, Finnish singer known by her stage name Katri Helena
- Markus Koistinen, retired Finnish shot putter
- Matti Koistinen, Finnish ice hockey player
- Otto Koistinen, Finnish kantele maker
- Petteri "Kode" Koistinen, Finnish guitarist, member of the Finnish rock band Neljä Ruusua
- Ritva Koistinen, Finnish kantele player
- Ville Koistinen, Finnish ice hockey player