Thielen

Thielen is a surname. Notable people with the surname include:


 * Adam Thielen (born 1990), American football player
 * Cynthia Thielen (born 1933), American politician
 * Friedrich Thielen (1916–1993), German politician
 * Hugo Thielen (born 1946), German journalist. author and editor
 * Jan Philips van Thielen (1618–1667), Flemish painter
 * Karl-Heinz Thielen (born 1940), German football player
 * Rob Thielen (born 1961), Dutch businessman