Leukemia is a malignant disease of bone marrow. Due to its high death rate it needs early diagnosis, prompt referral and medical treatment. Gingival enlargement is usually the first sign in specific types of leukemia. Here is a case report of 35 years old male presenting with gingival hyperplasia, gingival bleeding & systemic signs and symptoms of leukemia. This case report shows that gingival hyperplasia may represent an early manifestation of the underlying systemic disease. So the role of Periodontist in early diagnosis and prompt referral.