Abstract: 【Objective】In order to restore and grow the natural secondary Larix gmelinii forest in the Daxing’an Mountains, the forest was experimentally tended and intermittently cut to find the best way to conserve soil and water and to optimize the hydrological performance of the secondary forest. 【Method】In March 2007, experimental plots, in which the thinning intensity was 9.43%, 29.00%, 40.01% and 67.25%, and control plots were set. Field measurements were made during 2008-2017, and hydrological effects were evaluated in each soil layer and litter layer in 2017. These effects were used to describe the differences between various plots. The grey relational analysis was used to establish a comprehensive evaluation system of forest water retention performance. 【Result】 In the 8th year after thinning, the indexes showed some stability. In 2017, the soil bulk density of the plot with a thinning intensity of 40.01% was the lowest of all plot types, and the soil capillary porosity, total porosity and maximum water holding capacity were the highest. The non-capillary porosity of the plot with a thinning intensity of 67.25% was the highest, and there was a significant difference between this intensity and all others for every index except for capillary porosity(P< 0.05). The litter total volume and total maximum water holding capacity of the plot with a thinning intensity of 29.00% were the highest. The total natural water holding rate of the litter in the sample plots ranged from 100.52% to 144.37%, and the total water holding rate ranged between 494.79% and 673.97%. Litter total effective reserve rate and total effective storage capacity of the plot with a thinning intensity of 40.01% were the highest. At the same time, the water holding capacity of the litter increased logarithmically with an increase in soaking time, and the water absorption rate decreased with an increase in soaking time. The index weights of soil and litter were determined with the entropy weight method, and the hydrological perfor-mance of the forest was comprehensively evaluated with grey relational analysis. The degrees of correlation were thinning intensity 40.01%(0.85)>thinning intensity 29.00%(0.76)>thinning intensity 67.25%(0.55)>thinning intensity 9.43%(0.45)>thinning intensity(CK)(0.45). 【Conclusion】 After 10 years of thinning, the reform effect was obvious. The hydrologic performances of the soil layer and the litter layer were analyzed comprehensively, and performance was the greatest in the natural secondary forest of Larix gmelinii with a thinning intensity of 40.01%. Meanwhile, the hydrological performances of plots with four different levels of thinning intensity were all better than those of the control plots. It indicated that thinning had a positive effect, improving the hydrological performance of the woodland.