Suicidal behavior, including suicide attempt, may result from maladaptive explanatory patterns for past negative life events, in which a person attributes the causes of stressors to internal, stable and global factors. Conversely, an optimistic explanatory style involves perceiving negative life events as external, transient and specific, and may be related to reduced suicide risk. We examined the association between attributional style and lifetime suicide attempts in 135 college students, covarying age, race and ethnicity. Participants provided informed consent and completed an online survey. An optimistic explanatory style was associated with reduced risk of suicide attempt; this effect persisted in a model controlling for hopelessness and depressive symptoms. The manner in which an individual interprets negative life events may buffer against suicidal behavior. Therapeutic strategies to promote an optimistic explanatory style may be successful in the prevention of suicide.