The high rates of intimate partner aggression (IPA) among new parents may be partly due to changes in couples' division of household labor and childcare, which disproportionately negatively impact women. This is the first study to examine the association between division of labor dissatisfaction and IPA perpetration across genders, while also examining whether such dissatisfaction is specifically associated with IPA during conflicts about division of labor issues. Quarterly for one year, 109 women and 94 men from 111 couples with a first-born child approximately 32 months of age at study commencement described each incident of IPA that occurred during the quarter, including conflict topics and number of aggressive acts perpetrated. Division of labor and childcare comprised the largest portion (30%) of IPA conflict topics. Division of labor dissatisfaction at child age 24 months was positively associated with women's, but not men's, IPA perpetration during conflicts about division of labor issues, but not other topics. A similar pattern of results emerged in the examination of division of childcare dissatisfaction and conflicts about childcare vs. other topics. The discovery that the impact of division of labor and childcare dissatisfaction on IPA perpetration is context- and gender-specific suggests that, among women, a history of dissatisfaction may impair appropriate conflict resolution skills specifically when addressing domains of dissatisfaction. These findings support prevention of women's IPA via nonaggressive strategies for addressing division of labor concerns and promotion of equal opportunities for women and men at home and in the workplace during the early parenting years.