Mašek (feminine Mašková) is a Czech surname. Notable people include:
- Alexandru Masek, American semi-professional poker player with 9 Circuit rings
- Dominik Mašek (born 1995), Czech footballer
- Hana Mašková (1949–1972), Czech figure skater
- Ivan Mašek (1948–2019), Czech politician
- Jiří Mašek (born 1978), Czech footballer
- Kamilo Mašek (1831–1859), Czech composer, son of Kašpar
- Karel Vítězslav Mašek (1865-1927), Czech painter
- Kašpar Mašek (or Gašpar) (1794–1873), Czech composer
- Lukáš Mašek (born 2004), Czech footballer
- Martina Mašková (born 1998), Czech ice hockey player
- Pavel Mašek (1761–1826), Czech composer
- Václav Mašek (born 1941), Czech footballer