In order to eliminate the influence of acid value in solidification of waste cooking oil, the deacidification of waste cooking oil during solidification was advanced, and the optimized conditions, comprehensively considerated of deacidification and solidification, were as follow: 2mL sulfuric acid as catalytic agent was added in 50mL waste cooking oil, the temperature should be controlled at 45℃, the ratio of waste cooking oil and anhydrous alcohol was optimized to 1:3,and the time of reaction was 1 hour. Under the optimal conditions, the acid value of waste cooking oil was decreased from 21.5mg/g to 4.1mg/g, most of the impacts of acid value was eliminated in solidification of cooking oil. The production of solid fuel briquet was maximized to 101.5g using soybean cooking oil after deacidification, and the residue rate after burning was decreased to 16.7%.