Pile fermentation process is an important process in the manufacturing process of Sichuan dark tea. The horizontal tea fermenter was used to make Tibetan tea pile， and the sensory score and the content of main flavor components were used as indicators to study the effects of the temperature， time and moisture content of tea pile on its quality conversion. Based on the single factor test， the orthogonal test design with 3 factors and 3 levels was adopted. The best process parameters of the horizontal fermenter were obtained： temperature 70 ℃， time 110 h， and water content of tea blank 30%. The test results showed that compared with the traditional Woudui Tibetan tea， the equipment after the optimization of the parameters was rich in orange and red， and the taste was mellow and sweet， and the aroma was old. The sensory score was 92.95 points. GC-MS technology had detected 47 kinds of aroma components， with alcohols， aldehydes， alkanes and esters as the lord. The content of catechin component measured by HPLC technology was 5.52%， and the content of amino acid component was 9.257 mg/g. Under this process condition， the stacking period is shortened， clean production is realized， and the quality of Tibetan tea is improved.