OBJECTIVE: To evaluate the clinical effects of Shengmai Injection in treating coronary heart disease (CHD) based on correct syndrome differentiation and incorrect syndrome differentiation. METHODS: The patients' information was collected through a system of individual diagnosis and treatment of CHD. The score of main symptoms was calculated and recorded during the treatment. Patients were divided into two groups (incorrect syndrome and correct syndrome groups) on the basis of syndrome differentiation treatment or not. The clinical therapeutic effects of the two treatments were evaluated based on statistic theory combined with random walk method. RESULTS: There were 273 patients in the correct syndrome group and 4 patients died (case-fatality rate was 1.47%). There were 297 patients in the incorrect syndrome group and 7 patients died (case-fatality rate was 2.36%). In the correct syndrome group, random fluctuation peak of comprehensive evaluation index, walk steps, positive growth rate of walk, ratio, random fluctuation power-law, increase rate and record times of comprehensive evaluation index were 1 472, 13 617, 0.108 1, 9.25, 0.674 2, 0.470 6 and 3 128 respectively, while in the incorrect syndrome group, 1 030, 14 588, 0.070 6, 14.16, 0.660 6, 0.312 8 and 3 293 respectively. The random fluctuation power-law in both groups exceeded 0.5. CONCLUSION: There is a long-range correlation between the comprehensive evaluation index and therapeutic method as the CHD patients were treated with Shengmai Injection. The clinical therapeutic effects of Shengmai Injection under correct syndrome differentiation are better than the effects of Shengmai Injection under incorrect syndrome differentiation.