Abstract: Objective To explore the consistency of two methods, activity product ratio and EQUIL2 program, in estimating urinary supersaturation of common calcium salts, e.g., calcium oxalate and calcium phosphate, in patients with kidney stones in China. Methods The medical records of patients with kidney stones in Shanghai Ninth People 's Hospital afiliated to Shanghai Jiao Tong University School of Medicine during September 2015 to September 2020 were analyzed retrospectively. The dlinical data of 24 hours urine analysis were collected, and urinary relative supersaturation of calcium oxalate and calcium phosphate ( including brushite and hydroxyapatite) were calculated simultaneously by both of activity product ratio and EQUIL2 program. The correlation and consistency between the two methods were explored by analysis of correlation, linear regression and Bland-Altman agreement to estimate the urinary supersaturation of calcium oxalate and calcium phosphate. Results A total of 99 patients ( 53 males and 46 females ) with kidney stones were included in the study. The results of activity product ratio and EQUIL2 program showed good correlation in estimating urinary relative supersaturation of caleium oxalate (r=0.930, 95%CI :0.896 to 0.953, P<0.001), brushite (r=0.979, 95%CI: 0.969 to 0.986, P<0.001) and hydroxyapatite (r=-0.968, 95%CI: -0.979 to -0.952, P<0.001). The regression models in estimating urinary relative supersaturation of calcium oxalate ( adjusted R2 =0.904, P<0.001) and hydroxyapatite ( adjusted R = 0.936, P<0.001 ) showed high fiting degrees, but moderate fiting degrees for brushite ( adjusted R2 =0.749, P<0.001). Bland-Altman agreement analysis showed the difference value of the results of activity product ratio and EQUIL2 program mainly distributed between the 95% limits of agreement, indicating good consistency of both the methods in estimating urinary supersaturation of calcium oxalate and calcium phosphate. Conclusion Both the methods of activity product ratio and EQUII2 program have good consistency in estimating urinary supersaturation of calcium oxalate and calcium phosphate in patients with kidney stones in China.