Previous research has indicated that nightmares might be a common problem for people with psychotic symptoms. Furthermore, more distressing nightmares have been associated with higher levels of delusional severity, depression, anxiety, stress and working memory. However no known research has investigated the use of nightmare treatments in those with symptoms of psychosis. This study aimed to assess the acceptability and feasibility of using imagery rehearsal (IR) therapy as a treatment of nightmares for those presenting with co-morbid psychotic symptoms. Six participants presenting with frequent distressing nightmares and psychotic symptoms were recruited. Five participants attended 4–6 sessions of IR. Measures of nightmares, sleep quality, psychotic and affective symptoms were completed at baseline and immediately following the intervention. It was feasible to adapt IR for those experiencing psychotic symptoms. Descriptive improvements were noted on measures of nightmare-related distress, vividness and intensity. Positive post-session feedback endorsed the acceptability of IR. Nightmare frequency did not reduce following IR; however, participants described a change in emotional response. IR was an acceptable and feasible intervention for this small sample. A larger study powered to detect group changes, with an additional control is warranted to test the efficacy of the intervention for those with psychosis.