Background@#Early trauma is known to be a risk factor of suicide-related behavior. On the other hand, people who attempt suicide using a fatal method are reported to be more likely to complete suicide. In this study, we assumed that early traumaaffects an individual's temperament and character and thereby increases the risk of a fatal method of suicide attempts. @*Methods@#We analyzed 92 people with a history of previous suicide attempts. We compared the Temperament and CharacterInventory-Revised scores between the groups with and without early trauma, and between the groups with and without a history of suicide attempt using fatal methods through an analysis of covariance with age, sex, and presence of a psychiatric history as covariates. A mediation analysis was conducted of the relationship between early trauma and fatal methods of suicide attempt with self-transcendence as a mediator. @*Results@#Higher self-transcendence was reported in the fatal group (27.71 ± 13.78 vs. 20.97 ± 12.27, P = 0.010) and the early trauma group (28.05 ± 14.30 vs. 19.43 ± 10.73, P = 0.001), respectively. The mediation model showed that self-transcendence mediates the relationship between early trauma and fatal methods of suicide attempt. The 95% confidence intervals for the direct and indirect effect were (−0.559, 1.390) and (0.026, 0.947), respectively. @*Conclusion@#Self-transcendence may mediate the relationship between early trauma and fatal methods of suicide attempt. Self-transcendence may be associated with unhealthy defenses and suicidal behavior for self-punishment and may constitute a marker of higher suiciderisk.