Polycythemia vera is one type of myeloproliferative disorder which occurs due to the clonal proliferation of hematopoietic stem cell related to the production of leukocyte and megakaryocyte which produces a little less than erythrocyte. Polycythemia vera has a peak incidence in the sixth decade of life with males affected slightly more frequently than females. Vasquez first described polycythemia vera as an autonomous erythrocytosis in 1892, and a further description, delineation of the disease process and a complete course outline were made in 1899, 1903 and 1938, respectively. Symptoms include pruritus, tinnitus, vertigo, gastrointestinal (GI) pain, and bleeding gums. Hyperuricemia and hyperuricosuria are present in about 40% of these patients. Complications are hemorrhage, thrombosis, post-polycythemic myeloid metaplasia, and leukemic transformation. In case of surgery, complications such as hemorrahge and thrombosis are highly likable to happen. We report a case of preoperative and postoperative of a 63-year-old male, who was diagnosed as oral cavity cancer in the mouth floor, with known history of hypertension and polycythemia vera. We considered that conservative management would be an advisable treatment for patients with uncontrolled systemic disease.