Wentzel and Wentzell are surnames, and may refer to:
Wentzel Emil Wentzel (c. 1817–1892), timber merchant and politician in South Australia Gregor Wentzel (1898–1978), German physicist Stan Wentzel (1917–1991), Major League Baseball player Sune Wentzel (born 1971), Norwegian frisbee player Uta Wentzel (born 1979), German politician Volkmar Wentzel (1915–2006), American photographer
Wentzel may also refer to: Wentzel–Kramers–Brillouin approximation
Wentzell Alexander D. Wentzell (born 1937), Russian-American mathematician Fritz Wentzell (1899–1948), highly decorated German military leader during World War II
Wentzell may also refer to: Freidlin–Wentzell theorem, a statistics tool relating to Brownian motion