Abstract: This paper mainly studies the factors affecting the determination of active silicon content in gibbsite. Active silicon is an important index of gibbsite. A method for the determination of active silicon in gibbsite was established by inductively coupled plasma atomic emission spectrometry (ICP-AES). The sample pretreatment conditions were optimized, and the optimal sample weight, sample dissolution conditions, sodium hydroxide concentration and volume, constant volume, shaking frequency and boiling time were determined. The results show that the pressure dissolution sample can get better detection results. The recovery of the method is 99.13%~100.70%, the detection limit is 0.02 mg/L, and the relative standard deviation is 0.0191%. The method is simple, rapid, reproducible and accurate, which can be used for the determination of active silicon content in gibbsite.