Non-puerperal uterine inversion due to uterine sarcomas represents a very rare event with no reliable estimate of frequency in the literature. Clinically, the diagnosis of inversion may be difficult, as far as imaging procedures are concerned, although ultrasonography may prove to be useful. However, some characteristics such as the indentation of the fundic area and a depressed longitudinal groove extending from the uterus to the center of the inverted portion are difficult to recognize. Moreover, there is no specific computed tomography feature accurate enough to aid in the differential diagnosis. Here, we report a case of uterine inversion due to Müllerian uterine adenosarcoma whose preoperative workup and diagnosis took advantage of the application of magnetic resonance imaging.