Perfectionism, negative cognitive bias, and hopelessness were assessed among people hospitalized for depression (N = 121). Hopelessness and suicidal ideation were assessed 6 months after discharge. Path analyses indicated that higher perfectionism as an inpatient was directly associated with higher suicidal ideation 6 months later. Cognitive bias, in contrast, led to greater hopelessness 6 months later, which in turn led to higher concurrent suicidal ideation. Alternative models examined whether hopelessness partially or fully mediated the effect of perfectionism, whether hopelessness partially mediated the effect of cognitive bias, and whether inpatient depression and suicidal ideation severity explained the observed relationships. These alternative models were not supported. Perfectionism and negative cognitive bias both uniquely contributed to the prospective prediction of suicidal ideation.