Implicit stereotypes associating science with male might play a role in the development of gender differences in students' motivations for physical science. Particularly, the stereotypes of influential adults may induce students' regulatory foci and subsequently their motivational beliefs. Drawing on expectancy-value theory, this study investigated whether teachers' implicit science-is-male stereotypes predict between-teacher variation in males' and females' motivational beliefs regarding physical science. Results showed that teachers' implicit science-is-male stereotypes are positively related with males' self-concept and intrinsic value but negatively associated with females' motivational beliefs. The findings of this study corroborate the notion that teachers' implicit stereotypes can contribute to gender differences in motivational beliefs and probably also to gendered educational choices.