Context.— Plexiform fibromyxomas are uncommon gastrointestinal neoplasms that have histologic and molecular features that overlap with other gastrointestinal mesenchymal tumors and present a diagnostic challenge for surgical pathologists. Objective.— To provide a review of the clinicopathologic, morphologic, immunohistochemical, and molecular features of plexiform fibromyxomas, with a brief discussion of key features that aid in differential diagnosis. Data Sources.— Analysis of the pertinent literature (PubMed) and clinical practice experience based on institutional and consultation materials. Conclusions.— Plexiform fibromyxoma is a rare benign gastrointestinal mesenchymal tumor. Diagnosis is primarily based on morphology, immunohistochemistry, and the exclusion of other gastrointestinal mesenchymal tumors from the differential diagnosis.