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酚类物质是植物体重要的次生代谢产物，其含量不仅影响牧草的适口性和营养价值，还通过影响凋落物和根系分泌物的积累来影响土壤碳库的稳定。已有研究表明，放牧可以改变植被酚类物质的含量及组成，而现有研究对放牧是如何影响植被－土壤酚类物质组成和含量的关注还不够。为此，本研究以青藏高原东缘红原县境内的高寒草甸为研究对象，分析冬季放牧和禁牧下植被群落特征、植被和土壤(0 – 30 cm)酚类物质组成及含量的变化。结果发现：1)放牧减少了禾本科植物盖度，增加了毛茛科、蔷薇科以及蓼科等杂类草盖度。2)放牧降低了植被群落物盖度(P = 0.643)和0 – 20 cm土层土壤简单酚含量(P = 0.190)，显著减少了植被群落地上和地下生物量、地上部分简单酚含量及0－30 cm土层土壤总酚和单宁含量(P < 0.05)。3)放牧增加了植被群落物种丰富度(P = 0.357)和地下部分简单酚含量(P = 0.369)，显著增加了植被地上和地下部分总酚和单宁含量(P < 0.05)。本研究结果为保护和管理青藏高原高寒草甸健康持续发展提供了新思路。“,”As secondary metabolites of plants, polyphenols not only affect the palatability and nutritional value of forage, but also affect soil carbon stability through the accumulation of litter and root exudates in the soil. Previous studies have shown that grazing can change the content and composition of vegetation phenols, but few studies have specifically investigated the variation of vegetation-soil polyphenols under the influence of grazing. To fill this knowledge gap, an alpine meadow (grazing and grazing prohibition) in the Hongyuan county region of the Qinghai-Tibet Plateau was selected as the research object, where we analyzed the variation in vegetation community characteristics, composition, and content of polyphenols in the vegetal-soil system under winter grazing and grazing prohibition, respectively. The results showed that: 1) grazing decreased the coverage of grass, but increased the coverage of forbs such as Ranunculaceae, Rosaceae, and Polygonaceae. 2) Grazing decreased the coverage of the vegetation community (P = 0.643) and the concentration of simple phenol in the 0 – 20 cm soil layer (P = 0.190), and significantly decreased the biomass of the vegetation community (above- and belowground parts), the concentration of simple phenol in the aboveground part of vegetation, and the total phenol and tannin in the 0 – 30 cm soil layer (P < 0.05). 3) However, grazing increased the species richness of the vegetation community (P = 0.357), as well as the concentration of simple phenol in the belowground part (P = 0.369), and significantly increased the concentration of total phenol and tannin in the above- and belowground parts of the vegetation (P < 0.05). The results of this study provide a new idea for protecting and maintaining the healthy and sustainable development of alpine meadows on the Qinghai-Tibet Plateau.