OBJECTIVE To compare male and female medical students by age, level of education before admission to medical school, race/ethnicity, parental education level, socioeconomic status, and attitudes toward public health care. METHODS In 2001, we conducted an Internet-based survey of all students enrolled in the 16 medical schools across Canada. Based on the high response rate, first-year medical students at Canadian medical schools outside of Quebec were included in this analysis. The interactions between sex and age, years of premedical education, race/ethnicity, parental occupation, education and household income, impact of finances on choice of medical school, future specialty and practice location, attitudes toward private funding in the Canadian health care system were examined using descriptive statistics and chi2 tests. RESULTS There were no significant differences between male and female medical students in age, level of education before admission, and race/ethnicity. Female students' fathers (p=.046) and mothers (p=.061) were more likely to hold positions of higher occupational status than were those of male students. There was no significant difference between the parental household incomes of male and female students. Male students were more likely than female students to state that financial considerations would affect their choice of specialty (p=.002) and practice location (p=.002). Male students were more likely to express a positive attitude toward private funding in the health care system, both with respect to increasing the amount of private funding (p=.007) and the addition of private paying patients (p=.002). CONCLUSIONS Although women have almost reached equity with men in undergraduate medical education, female students are more likely than male students to have highly educated parents, suggesting that some barriers to access may still exist. The differences in attitudes of female and male medical students to finances and the public health care system become increasingly important as more women practice medicine. These sex differences need to be investigated further, as they could have implications for health policy.