Previous studies of the influence of family support on college students' academic performance have yielded inconsistent results. Therefore, the present study aimed to examine the link between family support and students' university-level academic performance in a more detailed way. First, we sought to clarify how two distinct aspects of perceived family support--social support and economic support--affect college students' academic performance. Second, we sought to determine how these two aspects of family support influence not only cumulative GPA scores but also the overall trend (slope) and stability (variability) of students' GPA scores across semesters. The participants in this longitudinal study were 240 university students (62 men, 178 women). The results revealed that the level of perceived family "social" support was important not only as a "main effect" predictor of the magnitude and stability of the students' GPA scores across three successive semesters, but also as a factor that helped female students to succeed regardless of their level of family economic support. In general, the data suggest that family social support is more important to women's success in college than to men's.