Posttraumatic stress disorder (PTSD) is a disabling psychological condition associated with significant physical comorbidities. There has been growing evidence to support the relationship between PTSD and cardiometabolic disease. Disordered eating behaviors often seen in people with PTSD symptoms may explain increased cardiometabolic risk. This systematic review aimed to assess the quality of evidence surrounding dietary intake of individuals with symptoms or a diagnosis of PTSD and their associated risk with cardiometabolic health outcomes. Online databases Scopus, ProQuest (Health), Embase, Medline, PsycINFO, and CINAHL with Full Text were searched for peer-reviewed English articles prior to December 2017 that examined dietary intake and cardiometabolic health outcomes in adults with PTSD symptoms or diagnosis. The quality of each study was graded based on the design and methodology using adapted quality assessment tools. Seven studies with five unique participant samples were included in the review. Study methods, design, populations, and outcomes were inconsistent across studies. Dietary intake was considerably varied and limited associations were demonstrated between dietary intake and cardiometabolic risk factors in the PTSD cohorts. Due to the variability of measures and study outcomes, there was insufficient evidence to determine the relationship between dietary intake and PTSD-related cardiometabolic health outcomes. Future studies are needed to examine these associations in individuals with PTSD: specifically higher quality descriptive studies are necessary to confirm a link between diet and cardiometabolic disease in PTSD.