Given the steady increase of ethnic diversity in the US, greater numbers of people develop the ability to negotiate ethnic boundaries and form multiple ethnic identifications. This paper explores the relationship between intra-ethnic and cross-ethnic relationships—defined in terms of social networks—and patterns of ethnic self-identification among New York City (NYC) Latinos. Drawing on theory and methods from the field of social network analysis, one hypothesis is that people with ethnically heterogeneous networks are more likely to have multiple ethnic identifications than people with ethnically homogeneous networks. The paper further explores the relationship between network ethnic diversity and the demographic and network characteristics of Latinos from four different Latino subgroups: Colombian, Dominican, Mexican, and Puerto Rican. A total of 97 NYC Latinos were administered ethnic self-identification and factorial surveys, and a social network questionnaire. Blau’s diversity index was used to compute the level of ethnic diversity present in participants’ networks. Results provided modest support for the hypothesis that multiple ethnic identifications would be associated with network ethnic diversity. There were important differences between the four groups in terms of network diversity, network ethnic composition, and ethnic self-identification. Results provide some support for the notion that weak ties introduce diversity to social networks.