Atypical polypoid adenomyoma is a rare benign tumor of the uterus that usually affects women of reproductive age and has an increased risk of progression into endometrial cancer. The pathogenetic mechanism has not been completely clarified. Due to the rarity of the tumor, current experience regarding the diagnostic and therapeutic approach is limited. For menopausal patients, hysterectomy seems to be the main treatment option. Our case concerns an asymptomatic menopausal patient with a vaginal delivery in her obstetric history and no hereditary history of gynecological cancer who came to the outpatient clinic for a gynecological examination. Transvaginal ultrasound revealed the presence of a large, round solid mass with increased vascularity within the endometrial cavity. A diagnostic dilation and curettage of the endometrium was performed. Histological examination of the endometrial biopsy showed an atypical polypoid adenomyoma, and it was decided to perform a total abdominal hysterectomy with bilateral adnexectomy. Histological examination of the surgical specimen of the uterus revealed no residual disease, no coexisting foci of atypical endometrial hyperplasia or endometrial cancer. The postoperative course was uneventful. The patient remains to this day under regular follow-up. The present case report highlights the significant difficulties involved in the preoperative diagnosis of atypical polypoid adenomyoma of the uterus and the difficult differential diagnosis from atypical endometrial hyperplasia and endometrial cancer, particularly in menopausal patients. At the same time, it is pointed out that despite its rarity, the early diagnosis of atypical polypoid adenomyoma, especially in young women, must be the main concern of the modern gynaecologist, in order to design the optimal treatment aimed at preserving fertility while avoiding the risk of recurrence of damage or malignant progression into endometrial cancer.