Abstract: The influencing factors on the peanut protein hydrolyzing by Alcalase to prepare peanut oligopeptides were studied, including protease dosage, substrate concentration, pH value, temperature and hydrolysis time etc. The regression models were established between the impact factors and the indexes, including the yield of oligopeptides and the degree of hydrolysis. Results indicate that the optimal processing conditions for preparing peanut oligopeptides with Alcalase are as follows: pH values 8.0, temperature 54℃, substrate concentration 4%, Alcalase dosage 3480 U/g, time 106 min. Under this conditions, peanut oligopeptides with the yield of oligopeptides 79.08%, the degree of hydrolysis 17.08%, the average length of peptides 5.85 and average molecular weight 661.5 are prepared.