Some researchers have shown a relationship between a sense of identity and Negative Affectivity (NA), while others have found that logical thinking errors contribute to NA. Additionally, a sense of identity is theoretically related to logical thinking erros. However, few studies have investigated the comprehensive relationship among sense of identity, logical thinking errors, and NA. The present study tested the hypothesis that a sense of identity affects NA directly, and has an indirect effect on NA through logical thinking erros. The participants were 202 undergraduates who completed a self-rating questionnaire. Structural equation analysis provided support for the hypothesis.