This study investigates the predictive influences of expectancies and values that may sustain students' dropout intentions in physics as well as gender differences in students' motivation and intention. Eccles's expectancy-value model was used to frame the study. The academic self-concept (expectancy component) and value components focusing on utility value, intrinsic value, and psychological costs were examined. A final sample of 61 students (31% female) enrolled in physics courses at a German public university participated. The study had a longitudinal design with two measurement points within one semester. A regression model revealed that a lower academic self-concept in physics predicted students' intention to drop out. However, subjective values did not predict dropout intention. Women had a lower academic self-concept and higher psychological costs than men did and saw less utility or intrinsic value in physics, whereas they did not want to drop out more often. The results highlight the need to close the gap between males' and females' expectancies and values regarding physics. Overall, these findings provide new insights into dropout intentions and gender differences in physics. The implications of these findings are discussed.