Suicide is a global problem whose causes have not been fully understood yet. Clearly, suicide is the result of complex interactions of various factors, yet Asian studies have reported social stresses and interpersonal problems as more important contributors. The purpose of the present study is to develop a model to predict suicidal ideations based on perceived social support, thwarted belongingness, and perceived burdensomeness as the variables. The research method is correlational and the statistical population consists of single 20-30year-old girls in Isfahan City chosen by multistage clustering sampling. The sample size included 239 participants and the research tools were the multidimensional scale of perceived social support (Zimet, Dahlem, Zimet & Farely, 1988), and the suicidal ideations (Reynolds, 1987-1988 quoted by Beaumont, 1994) questionnaires. Studying the general fitting of the recommended model was performed by AMOS-22 statistical software. The research results indicated that the social support of family predicts suicidal ideations through thwarted belongingness and perceived burdensomeness directly and indirectly, and friends'__AWT_NOKT_COMMA__ support predicts it indirectly through thwarted belongingness. However, the relationship between support of significant others and suicidal ideations was not verified. The results also suggested the relatively different role of family and friends in development of suicidal ideations, but generally increase in the social support of family and friends can inhibit suicidal ideations.