Uterine mesenchymal tumors are developed from the endometrial stromal cells and uterine smooth muscles. Endometrial stromal tumors (EST) are constituted of cells that simulate the endometrial stroma of the non-neoplastic proliferative phase of uterus. They are comprised of less than 10% of uterine tumors. WHO classified smooth muscle tumors as three broad heading that include: leiomyoma, leiomyosarcoma and smooth muscle tumor of uncertain potential. This chapter focuses on the leiomyosarcoma, myxoid variant, epithelioid leiomyosarcomas, and uterine smooth muscle tumors of uncertain malignant potential. This chapter also discusses the perivascular epithelioid cell tumors, adenomatoid tumor, and adenomyosis and adenomyoma, Uterine tumors resembling ovarian sex cord-like elements are also discussed in this chapter. Five well-illustrated tables and 34 well-labeled figures are also presented in this chapter.