In order to develop the rice hull hot briquetting technology and machine, the ef fect of briquetting pressure, heating temperature, moisture and the ratio of ric e hull to binder on briquetting laxation density was studied based on the quadra tic regression orthogonal rotation tests with four factors and response face met hod. Functional models of briquetting laxation density were established and anal yzed by SPSS 115 and Matlab 71. The results showed that the effect order of fo ur factors was as follows: heating temperature, moisture, briquetting pressure , and ratio of rice hull to binder. When briquetting pressure, ratio of rice hul l to binder, moisture, and heating temperature were 10MPa，35〖DK〗∶1，16% ， and 100℃ respectively, the optimum conditions were obtained and the briquetting lax ation density reached to 0945g/cm3, which was suitable to briquetting. The regression equation was significant, and the mathematical model for the simulat ion was presented. 