Abstract: Plant community composition and interspecific associations reflect inter-dependence and competition between species, influencing their spatial distribution. To explore the evolutionary trends and stability mechanisms of grassland communities influenced by the interaction between yak dung depositions and vegetation we analyzed the importance values (IV) of different species, Jaccard association indices and Spearman rank correlation coefficients of the main species present in patches of grass/forb and Kobresia/forb swards under yak dung deposition in an alpine meadow on the northeast Qinghai-Tibetan Plateau. The results indicated that: 1) dung deposition (DP) increased the Agropyron cristatum IV and decreased the Stipa krylovii IV in grass/forb patches, while decreasing the Kobresia capillifolia IV for Kobresia/forb parches; 2) in grass/forb patches, the species-pairs ratios of positive and negative associations under DP and control (CK) were 0.61 and 0.63, respectively and their respective associated species-pairs were 6.6% and 6.4%. For Kobresia/forb patches, the species-pairs ratio of positive and negative associations in DP and CK were 0.90 and 0.72, respectively and their respective associated species-pairs were 2.8% in DP and 14.5% in CK, exhibited mainly between the dominant or sub-dominant species and the companion species; 3) the interspecific association of most species-pairs was weak in both vegetation types; yak dung strengthened the stability of Kobresia/forb patches benefiting the generation of grass/forb patches; 4) according to their adaptability to environment and the key ecological factors affecting plants, the main plant species of two patches were divided into three ecological groups: shade-intolerant and drought-tolerant plants, shade-tolerant and drought-intolerant plants, and, shade-intolerant and drought-intolerant plants.