The invention relates to a composition of a microbial fermentation product containing chenodium quinoa seeds and application of the composition in a hair care cosmetic. The invention provides the composition of a yeast fermentation product extract and the microbial fermentation product containing the chenodium quinoa seeds. According to the composition, the yeast fermentation product extract richin organic acids, amino acids, small molecule active peptides and other components and the microbial fermentation product containing the chenodium quinoa seeds are selected for promoting the metabolism of the head, unblocking hair follicles, nourishing the hair and controlling oil to treat the hair symptoms, and meanwhile mulberry fruits, radix angelicae sinensis, radix astragali, rhizome chuanxiong, poria cocos and other kidney-nourishing and liver-tonifying medicines are selected for nourishing the kidney and tonifying the liver to strengthen the hair foundation.