Abstract: To shorten the duration of hemp degumming and increase the fiber quality, microbial and steam explosion united degumming technique was studied. In this study, hemp was treated by fast retting using Dm111 strain and followed by steam explosion treatment. Different parameters of this technique were tested. The results indicated the best united-degumming conditions were: during the microbial retting, hemp was incubated with Dm111 strain at 35℃ shaking-flask 180 rpm（revolutions per minute）for 6 hours; And the steam explosion was performed in a holding-time of 120 seconds and a pressure of 2.5MPa. After treated by this technique, the analysis data showed that the cellulose of hemp was 77.01%, and the pectin, hemicelluloses and lignin were removed by 89.15%, 33.75% and 30.64%, respectively. The degree of fiber separation was 689 mm/mg and the strength of fiber was 80N.