Fresh leaves from summer-autumn tea were directionally fermented through artificial inoculation with Eurotium cristatum to increase the utilization efficiency of fresh leaves from summer-autumn tea trees and improve the quality of summer-autumn tea. The effects of different conditions including the content of water， the amount， temperature， and time of inoculation on the sensory quality and physicochemical components of tea fermented by Eurotium cristatum were studied. The results showed that the sensory quality of tea fermented by Eurotium cristatum was optimal with an inoculation amount of 1.5×10? CFU， water content of 30% in rolled leaves， fermentation temperature of 28 °C， and fermentation time of 8 days. The tea produced under these conditions exhibited vigorous growth of “golden flowers”，a rich and pure fungal aroma， a yellowish-orange and bright infusion， and a mellow and sweet-aftertaste flavor. The content of tea polyphenols， water extracts， soluble sugars， free amino acids， and theaflavins in fermented summer-autumn tea decreased to varying degrees， with reductions of 23.38%， 17.42%， 47.18%， 30.41%， and 9.30% compared with that in unfermented summer-autumn tea. The content of thearubigins and theaflavins significantly increased by 31.53% and 21.10%， respectively. It is indicated that the fermentation with Eurotium cristatum can significantly improve the quality of summer-autumn tea， which is helpful for the development and utilization of summer-autumn tea resources.