Objective：To investigate correlation between the serum concentrations of CCN1 protein and its clinical features，and to explore the diagnostic value of CCN1 in early acute myeloid leukemia（AML） patients. Methods：Sandwich enzyme-linked immunosor－bent assay（ELISA） was applied for detecting the concentrations of serum CCN1 protein in 96 early AML patients and 159 control healthy people. ROC curve was used to assess the diagnostic value of CCN1 in early AML patients. The concentrations of serum CCN1 between the distinct clinical features groups and the classification groups were compared. Results：The concentrations of serum CCN1 protein in 96 early AML patients were significantly lower than those in healthy controls（P=0.000）. The area under the ROC curve was 0.823，and the optimal cut-off value was 101.22 pg/mL（sensitivity=0.823，specificity=0.667）. The concentrations of serum CCN1 protein had no correlation with clinical features. There were significant differences between different AML classification types and the control groups（P=0.000），but no significant difference was observed among CCN1 of AML types（P >0.05）. Conclusion：The concentrations of serum CCN1 protein in early AML patients are significantly different from those in control groups，which suggests that serum CCN1 protein concentration is a biomarker with broad application prospect for early AML diagnosis.