Leiomyosarcoma is a malignant mesenchymal tumor that is very uncommon in the conjunctiva. Nevertheless, we describe here the clinical manifestations, management, and prognosis of a rare case of leiomyosarcoma in this location. An 81-year-old male presented at a tertiary hospital with a rapidly growing mass. After performing biopsy, histopathological examination revealed the existence of a conjunctival leiomyosarcoma. On this diagnosis, a thorough metastatic screening was performed showing no enlarged lymph nodes or metastatic deposits anywhere in the body. To treat the condition, we performed an evisceration with clear margins and subsequent radiotherapy.