With dandelion as raw materials, the bacteria were isolated and identified , and the total acid, pH and salinity were also identified from the naturally fermented product. Free amino acids were analyzed by amino acid analyzer and were classified in accordance with the taste intensity. The results showed that Lactobacillus planetarium was dominant and the content of bitter amino acids (Leu, Val, Arg, Ile, Trp, Met) was higher than the others in the early fermentation process. Lactobacillus planetarium and Lactobacillus brevis took an active part in the main fermentation stage. Meanwhile, the content of sweet amino acids (Ser, Thr, Gly, Ala, His, Pro) and umami amino acids (Glu, Asp, Lys) increased but the bitter amino acids' content decreased. In the late fermentation process, Lactobacillus fermentum was dominant, and the sweet and umami amino acids' content was higher than the bitter. Throughout the fermentation process, the content of aromatic amino acids (Tyr, Cys, Phe) changed a little. Dandelion enjoyed a best taste from the seventh to twentieth day after fermentation.