Abstract: Abstract: The inhibition of N-nitroso compounds formation and scavenging effect to sodium nitrite by the extracts of Tetradium ruticarpum and Glycyrrhizae were investigated. The optimum condition on extracting active components of grape seeds were determined by L9 (33) orthogonal test. The results showed that when consider the scavenging rate as the main index, the optimum extraction conditions of Tetradium ruticarpum were as followed: the ratio (W/g:V/mL) of solid (Tetradium ruticarpum) to solution (50% Ethanol) is 1: 50, the extraction was proceeded for two and half hours using refluxing. Under those conditions, the maximum capacity of scavenging effect to sodium nitrite were 0.8365. While the optimum extraction conditions of Glycyrrhizae were as followed: the ratio (W/g:V/mL) of solid (Glycyrrhizae) to solution (70% Ethanol) is 1: 50, the extraction was proceeded for one and half hours using refluxing. Under those conditions, the maximum capacity of scavenging effect to sodium nitrite were 0.5580. When consider the disconnection rate as the main index, the optimum extraction conditions were as followed: the ratio of solid (Tetradium ruticarpum) to solution (60% Ethanol) is 1:50, the extraction was proceeded for two and half hours in 80℃. Under those conditions, the maximum capacity of inhibit the N-nitroso compounds formation were 0.9228. While the optimum extraction conditions were as followed: the ratio of solid (Glycyrrhizae) to solution (60 % Ethanol) is 1:50, the extraction was proceeded for two and half hours in 60℃. Under those conditions, the maximum capacity of inhibit the N-nitroso compounds formation were 0.6256.