Objective: DRGs combination of hospital charges of patients undergoing cardiac surgery. Methods: a regression tree model was established to analyze the data of 4216 patients undergoing cardiac surgery in 39 general hospitals in Henan Province (Year 2014). Results: a total of 9 DRGs groups were generated in the model, Reduction in Variance(RIV)was 0.5468, Coefficient of Variation(CV) was between 0.129-0.435.Conclusion:the regression tree model provide a good basis on the DRGs grouper of patients undergoing cardiac surgery.