To examine the association between maternal education and excessive gestational weight gain (EGWG) and whether this association differs by maternal race/ethnicity and neighborhood socio-economic status (SES). A sample of 56,911 New York City births between 1999 and 2001 was used. Self-reported EGWG was defined as gaining >40 pounds. Maternal education and race/ethnicity were obtained from birth record data. Neighborhood SES was determined from 2000 US Census data. Women with a high school [prevalence ratio (PR) = 1.21; 95 % CI 1.10-1.32] and some college (PR = 1.33; 95 % CI 1.21-1.47) education were more likely to gain excessive weight during pregnancy than their counterparts with less than a high school education. Having a college or more education was associated with a decreased EGWG for non-Hispanic white women (PR = 0.81; 95 % CI 0.67-0.96) but an increased EGWG for Hispanic women (PR = 1.25; 95 % CI 1.12-1.44). EGWG increased for women with a college or more education in medium and low SES neighborhoods (1.26; 95 % CI 1.04-1.53 and 1.20; 95 % CI 1.10-1.30, respectively); whereas a college or more education was not significant in the high SES neighborhoods. Our findings suggest that maternal education is associated with EGWG. However, this association depends on race/ethnicity and SES of the neighborhood of residence.