[Objective] In order to provide theoretical basis for forest hydrological effect study, the experiment was conducted to investigate the growing stock and water retention capability of forest litter at different stand ages group in Daxing'an Mountains.[Methods] We chose Xing'an forest larch with different stand ages as the object, and set the standard sample. The method of water immersion was used to measure the water retention capability of litter. We then calculated the effective retaining content and the maximum water-holding capacity.[Results] The litter volume of four different stand age groups was from 28.03 to 34.32 t/hm², and the maximum water-holding capacity was from 87.09 to 87.09 t/hm². The maximum water-holding capacity increased with the increase of litter volume, and the maximum water-holding capacity in the half-decomposed layer was greater than that in the undecomposed layer. By statistical analysis, there was a logarithmic relationship between water capacity of undecomposed and half-decomposed layer and immersion time, and there was an exponential relationship between water absorption rate and immersion time. Overall, the rainfall interception capacity of half-decomposed layer was better than that of undecomposed layer.[Conclusion] Significant difference has been found in forest litter volume among Xing'an larch with different ages excepting which of the mature forest and near-mature forest, the rainfall interception capacity of mature forest, near-mature forest and middle-aged forest was greater than that of young forest.