Based on social control perspectives and results from prior studies we test hypotheses about the extent to which characteristics of family and social networks are associated with substance use disorders (SUD), and whether these associations vary by sex. In this study SUD is alcohol or illicit drug abuse or dependence as defined by criteria of the Diagnostic and Statistical Manual of the American Psychiatric Association. With nationally representative data of adult Latinos from the National Latino and Asian American Survey (NLAAS), we found that respondents' language use with family, rather than language proficiency, appears to be a more efficient proxy for social assimilation to represent differential levels of risk of SUD. SUD was positively associated with problematic family relations for men but not women, and SUD was positively associated with more frequent interactions with friends for women but not men. The results suggest that the salient features of social assimilation associated with SUD include the context of language use and transformations in family and social network relationships that differ in important ways between Latino men and women.