Objective:To discuss the diagnosis and differential diagnosis of granulocytic sarcoma(GS).Methods:Six cases were reported in this paper.They were assessed by pathologists.Immunohistochemistry(IHC) stain and routine hematoxylin and eosin(H&E) stain were applied.Results:All patients involved in different anatomic sites respectively including skin,lymph node,soft tissue,breast,cervix and penis.All cases were previously error diagnoses.Three of them were initially diagnosed as non-Hodgkin lymphoma(NHL).One case of cervical lymph node lesion was first considered as metastasized carcinoma by clinician.One biopsied skin sample was initially reported as Karposi’s sarcoma.And one breast case was suspicious of the lobular carcinoma with the frozen samples without antecedent clinical history information.GS was accompanied with acute myeloid leukemia(AML) in one case and with acute lymphocytic leukemia(ALL) in one case.Histopathologically,blastic,immature and differentiated variants were found in four,one and one,respectively.Immunohistochemistry(IHC) showed that myeloperoxidase(MPO) and lysozyme were both found to be positive in all cases,CD43 was found in 5 of 6 cases.Three of six cases were CD68,CD15 and LCA positive.CD34 and CD117 were positive in 1/5 and 1/6 cases,respectively.However,CD20 and CD3 were negative in all cases.Conclusion:GS was uncommon and it may be misdiagnosed easily in routine practice.Each area had its own character,but they had the common features too.It can be correctly diagnosed by combination of H&E stain,IHC stain,peripheral blood and bone marrow.MPO and Lysozyme were necessary for the nature of granulocytes.In addition,CD43,CD68 and CD15 were very helpful. Objective: To discuss the diagnosis and differential diagnosis of granulocytic sarcoma (GS). Methods: Six cases were reported in this paper. They were assessed by pathologists. Immunohistochemistry (IHC) stain and routine hematoxylin and eosin (H & E) stain were applied. Results All patients involved in different anatomic sites respectively including skin, lymph node, soft tissue, breast, cervix and penis. All cases were previously error diagnoses. Three of them were initially diagnosed as non-Hodgkin lymphoma (NHL) .One case of cervical lymph node lesion was first considered as metastasized carcinoma by clinician. One biopsied skin sample was initially reported as Karposi’s sarcoma. One and one breast case was suspicious of the lobular carcinoma with the frozen samples without antecedent clinical history information. GS was accompanied with acute myeloid leukemia (AML) in one case and with acute lymphocytic leukemia (ALL) in one case. Histopathologically, blastic, immature and differentiated variants were found in Four, one and one, respectively. Immunohistochemistry (IHC) showed that myeloperoxidase (MPO) and lysozyme were both found to be positive in all cases, CD43 was found in 5 of 6 cases. Threatened six cases were CD68, CD15 and LCA positive CD34 and CD117 were positive in 1/5 and 1/6 cases, respectively. However, CD20 and CD3 were negative in all cases. Conlusion: GS was uncommon and it may be misdiagnosed easily in routine practice. Since the area had its own character , but they had the common features too. It can be correctly diagnosed by combination of H & E stain, IHC stain, peripheral blood and bone marrow. MPO and Lysozyme were necessary for the nature of granulocytes. In addition, CD43, CD68 and CD15 were very helpful.