Abstract: Reaction properties of L-asparaginase immobilized on chitosan modified with polyethylene glycol were studied in this paper. The effects of substrate concentration, quantity of immobilized L-asparaginase, temperature, rotation rate on the batch reaction were investigated. Effects of substrate concentration, volume rate, temperature, height of enzyme column on the continuous reaction were investigated. The results show that under the proper conditions the immobilized L-asparaginase has good properties for hydrating asparagine from buffer.