This study examines suicidal ideation among Asian immigrant adults in the United States, with consideration of the roles of acculturation and social support. Using the 2002-2003 National Latino and Asian American Study (NLAAS), I conduct latent class analysis with measures of U.S. cultural orientation and Asian ethnic affiliation to create a multidimensional construct of acculturation. Three acculturation groups are identified (assimilated, integrated, separated) that show different associations with suicidal ideation. Then I analyze how the association between acculturation status and suicidal ideation is moderated by social support, distinguishing between perceived versus received support. Findings reveal that the buffering role of social support is gender-specific, with perceived support from friends reducing the risk of suicidal ideation only among assimilated women. Implications for future research include further application of acculturation as a multidimensional construct to various health outcomes and behavior as well as to other immigrant subgroups. Public health intervention efforts aimed at preventing suicide should endeavor to promote perceptions of an available social support system among immigrants, and aid in establishing sources of support outside the family particularly for immigrant women.