Hippophae rhamnoides subsp. yunnanensis Rousi is an important ecological and economic tree in southeastern Xizang, however, there is very few seedlings under its forest. To investigate the effects of leachates from litter at different decomposition stages on seed germination, this study measured the germination rate, germination potential, germination index, vigor index, germination rate coefficient, germination initiation time, seedling fresh weight, and radicle length of seeds treated with leachates from seven mass concentration gradients (0, 2, 5, 10, 25, 50 g/L and 100 g/L) of undecomposed litter, semi-decomposed litter, and fully decomposed litter. Additionally, the comprehensive allelopathic effect index of different treatments was evaluated. The results indicated that: (1) High concentrations of undecomposed (10-100 g/L), semi decomposed (5-100 g/L), and fully decomposed (50-100 g/L) litter extracts can prolong the seed germination initiation time by 0.67-4.67 days, whereas the leaching solution of fully decomposed litter with a concentration range of 5-10 g/L advanced 0.67-1.00 days of seed germination initiation time. (2) The effects of three types of litter extraction solutions on seed germination potential, germination index, and germination rate coefficient showed an increasing inhibitory effect with the concentration of the extraction solution, but the effects on vitality index, seedling fresh weight, and embryonic root length showed a "low promotion and high inhibition" pattern; The germination rate showed an increasing inhibitory effect with the concentration of undigested and semi decomposed litter extract, while under the treatment of fully decomposed litter extract, it showed a "low promotion and high inhibition" effect. (3) The comprehensive effect index of allelopathic extracts of different concentrations of undecomposed, semi decomposed, and fully decomposed litter ranged from -2.01-0.04, -6.39-0.00, and from -0.72-0.01, respectively, indicating that semi decomposed litter had the strongest allelopathic inhibition effect on seed germination, followed by undecomposed litter and fully decomposed litter. The excessive accumulation of allelopathic substances released from litter in the forests of H. rhamnoides subsp. yunnanensis inhibited seed germination, which is not conducive for its population renewal. There results can provide scientific reference for the renewal of natural forests and sustainable management of artificial forests of H. rhamnoides subsp. yunnanensis.