Abstract: Through the laboratory examination results of a case with HbH complicated with G6PD deficiency in acute hemolysis，to analysis the interaction of hematology parameters when the two diseases exist at the same time and complicated with acute hemolysis，and investigates the meaning to diagnosis and therapy. Through this case，obtains the conclusions as below：（1） In hemolytic patient，with MCV normal or higher，it can not exclude the possibility of thalassemia，and need to have further examination to confirm；（2）In acute hemolysis，with G6PD normal，it can not exclude the possibility of G6PD deficiency，need to reexam G6PD 1 month after acute hemolysis become normal，to obtain the real result. The clinical diagnosis and therapy can not believe the temporary results of laboratory fanatically，and should consider comprehensively，so cautiously treats the hemolysis and avoids becoming worse. Because that the both two are genetic disease，the most effective way to prevent and treat the disease are antemarital physical examination and prenatal examination so as to avoid the birth of infant with the defect.

Key words: G6PD deficiency, HbH, acute hemolysis