Seppänen is a Finnish surname derived from the occupation of blacksmith ("seppä"). Notable people with the surname include:

• Elias Seppänen (born 2003), Finnish racing driver
• Ensio Seppänen (1924–2008), Finnish sculptor and professor
• Esko Seppänen (born 1946), Finnish politician
• Iiro Seppänen (born 1975), Finnish producer, director and author
• Sara Seppänen (born 1982), Finnish politician
• Timo Seppänen (born 1987), Finnish ice hockey player
• Tytti Seppänen (born 1980), Finnish politician