Abstract: This study was designed to evaluate the nutritional characteristics and percentage of released nitrogen ( %) of silkworm pupae proteins and peptides after simulated gastric and intestinal digestion, with a view to use in animal feeds or human nutritional support.Distribution of amino acids in the processed protein was analyzed and the amino acid score, chemical score, and essential amino acid index ( EAAI) were calculated. The method of simulated gastrointestinal digestion in vitro and Kjeldahl determination were used to analyze absorption characteristics and the released nitrogen ( %) of samples. Silkworm pupae proteins and peptides contained all amino acids required by humans, and the composition was reasonable. Simulated gastrointestinal digestion resulted in about 90% nitrogen release amount. The data indicated that this protein might be useful as an economic, high quality supplement in animal feeds and for human nutritional support.