Inflammatory myofibroblastic tumors (IMTs) of the uterus are relatively rare. Although most IMTs exhibit indolent biological behaviors, local recurrence, and metastasis may occur. Such patients may benefit from targeted therapy; therefore, precise diagnosis is essential for clinical follow up and treatment. Here, we describe a 33-year-old woman with a uterine mass that was detected 4 years previously during pregnancy. The morphology of the tumor resembled that of a uterine leiomyoma, lacking myxoid matrix, and inflammation. Following immunohistochemical and molecular analyses, the tumor was definitively identified as a uterine IMT based on its morphological features. The uterine IMT described in this case had a rare morphology, which can be easily misdiagnosed based on histology alone. Hence, understanding the morphological changes of IMTs in greater detail is imperative to facilitate their accurate diagnosis.