[Objective] To study the ultrasonic extraction technology of sterol from the rhizome of Begonia grandis Dry. subsp. sinensis ( A. DC. ) Irmsch. .[Method]In this study,the sterol was first extracted from B. grandis rhizome using ultrasonic technology,and then quantitatively analyzed using the advancedLiebennann-Bur chard colorimetric method. The single factor experiment and orthogonal experiment were carried out to study the effects of factors including extraction temperature,extraction time and solid-liquid ratio on the yield of sterol. The regression equations to three factors were established by RSREG software in SAS8.1. In addition,the types of sterols were analyzed using HPLC. [Result]Results show that the regression equation was significant,the optimal technological conditions of sterol extraction were as follows: extracting temperature was 58 ℃ ,extracting time was 57 min,solid-liquid ratio was 1: 44 ( g / ml) . Under these conditions,the content of sterol was 1. 80 mg / g in the rhizome of B. sinensis. [Conclusion]Ultrasonic-assisted technology is an efficient,energy-saving and time-savingmethod that can be used to extract sterol from the rhizome of B. grandis. In addition,the analysis of HPLC spectrum reveals that sterol composition in the rhizomeof B. sinensis is complex,including β-sitosterol and other sterols. [Objective] To study the ultrasonic extraction technology of sterol from the rhizome of Begonia grandis Dry. Subsp. Sinensis (A. DC.) Irmsch. [Method] In this study, the sterol was first extracted from B. grandis rhizome using ultrasonic The single factor experiment and orthogonal experiment were carried out to study the effects of factors including extraction temperature, extraction time and solid-liquid ratio on the yield of sterol. The regression equations to three factors were established by RSREG software in SAS 8.1. In addition, the types of sterols were analyzed using HPLC. [Result] Results show that the regression equation was significant, the optimal technological conditions of sterol extraction were as follows: extracting temperature was 58 ° C, extracting time was 57 min, solid-liquid ratio was 1: 44 (g / ml). Under these conditions, the content of sterol was 1. 80 mg / g in t Ultrasound-assisted technology is an efficient, energy-saving and time-saving method that that can be used to extract sterol from the rhizome of B. grandis. In addition, the analysis of HPLC spectrum reveals that sterol composition in the rhizomeof B. sinensis is complex, including beta-sitosterol and other sterols.