The present study uses a within-group controlled design to examine the efficacy and safety of two psychological approaches to posttraumatic stress disorder (PTSD) in 10 patients with a concurrent psychotic disorder. Patients were randomly assigned either to prolonged exposure (PE; N = 5) or eye movement desensitization and reprocessing (EMDR; N = 5). Before, during, and after treatment, a total of 20 weekly assessments of PTSD symptoms, hallucinations, and delusions were carried out. Twelve weekly assessments of adverse events took place during the treatment phase. PTSD diagnosis, level of social functioning, psychosis-prone thinking, and general psychopathology were assessed pretreatment, posttreatment, and at three-month follow-up. Throughout the treatment, adverse events were monitored at each session. An intention-to-treat analysis of the 10 patients starting treatment showed that the PTSD treatment protocols of PE and EMDR significantly reduced PTSD symptom severity; PE and EMDR were equally effective and safe. Eight of the 10 patients completed the full intervention period. Seven of the 10 patients (70%) no longer met the diagnostic criteria for PTSD at follow-up. No serious adverse events occurred, nor did patients show any worsening of hallucinations, delusions, psychosis proneness, general psychopathology, or social functioning. The results of this feasibility trial suggest that PTSD patients with comorbid psychotic disorders benefit from trauma-focused treatment approaches such as PE and EMDR.