Most research evaluating eye movement desensitization and reprocessing (EMDR) therapy has taken place in community settings, leaving the impact for service users within inpatient environments less clear. This systematic review sought to identify, summarize, and critically evaluate studies that investigated the impact of EMDR on symptoms of posttraumatic stress disorder (PTSD) within adult inpatient mental health settings. Seven databases were systematically searched to identify published and unpublished articles eligible for inclusion. Eleven studies, published between 1995 and 2020, were included within this review. All studies showed that EMDR improved PTSD symptoms, across a variety of study populations. However, these findings are limited by the (a) preponderance of case study designs (preventing causal attribution); (b) provision of synchronous treatments; (c) poor methodological quality; and (d) high heterogeneity across studies. Prior research has shown EMDR’s effectiveness and safety for vulnerable populations. While the evidence is beginning to support its use with those experiencing PTSD symptoms within adult inpatient settings, it is premature to strongly recommend it as a routine intervention. Future research within this area is recommended.