Objective To discuss the value of serum thymidine kinase 1 and DNA ploidy for the diagnosis of patients with acute myeloid lecukemia.Methods Determined TK1 and DI in 20 healthy people,6 patients with benign proliferate in hematological system and 66 patients with acute myeloid lecukemia by chemiluminescence detection technique and flow cytometry.Nonparametric comparisons among three group were done by rank sum test.ROC curve was used to determine the AUC and the diagnosis value serum thymidine kinase 1 and DNA.Results As showed by peripheral blood results,the TK1 (x2 =36.877,P＜0.001) and DI (x2=4.040,P＜0.05) had statistically difference among healthy people group,patients with benign proliferate in hematological system group and AML group.The normal control group compared with the AML group,TK1 (Z=-6.073,P＜0.001)and DI (Z=-2.012,P =0.044) had statistically difference;The normal control group compared with the benign proliferate patients,TK1 (Z=-1.234,P =0.169) and DI (Z=-1.084,P =0.278) had no statistically difference.The benign proliferate patients and that with AML patients,TK1 (Z=2.177,P=0.036) had statistically difference,but DI (Z=-1.801,P=0.061) had no statistically difference.The TK1 and DI area under the ROC curve were 0.950 (P＜0.001) and 0.638 (P=0.063),best cut-off were 1.73 pmol/L and 0.98,sensitivity were 0.95,0.78,and specifity were 0.88,0.39.Conclusion Serum TK1 and DI is a important diagnostic marker of early for AML patients,TK1 have a better diagnostic performance than DI significantly.