Inflammatory myofibroblastic tumor (IMT) is a rare soft-tissue neoplasm of unknown etiology. It mimics, clinically and radiologically, malignant tumors. Histologically, this tumor is composed of differentiated myofibroblastic spindle cells accompanied by an inflammatory infiltrate, with numerous plasma cells and/or lymphocytes. Initially described in the lung, numerous extrapulmonary sites of this tumor have been found but appendiceal IMT is rare, especially in adult women. In this study, we aimed to examine the literature as well as to describe a case of a 42-year-old woman that we operated on that presented as an appendiceal mass that obstructed the lumen of the appendix and caused acute appendicitis. Upon histopathological examination, the lesion was identified as an IMT. Awareness of this type of tumor in the differential diagnosis of appendiceal masses, avoids overtreatment, and highlights the need of long-term follow-up regarding the tendency for local recurrence and small risk of distant metastasis.