Haemoglobin (Hb) H is moderately severe disease resembles thalassemia intermedia with mild splenomegaly. Because Hb H is unstable and precipitate within the red cell, hemolysis occurs. This is a report of 4 cases of Hb H disease. Hb H was demonstrated by incubation of blood with supravital oxidizing stains such as %1 brilliant cresule blue.Hb electerophorisis of freshly prepared hemolysate at alkaline PH demosterated a fast moving component amounting 5-30 of total Hb. CBC showed low Hb, Low MCV, Low MCH, Low MCHC, and high RDW, Normal to high RBC count. The typical patients were generaley anemic with Hb of 8-10 g/dl, one patients had Hb level as Low as 5.5 g/dl (case 3), the complication of Hb H disease were those related to chronic hemolysis, jaundice, hepato spleenomegaly, folate deficiency, and suseptibility to infection (case 4). Hemolytic episodes is probably precipitated by drugs or infection (case 3,4).Hb H disease consistent with beningn course. Growth, maturation, marriage, pregnancy, empolyment, are with in normal limits. Therapy inculudes supplementation with folic acid, avoidence of oxidant drugs prompt treatment of infection episodes by antibiotics, and in case of anemia use transfiusion as paliative treatment.