Methionine is one of the basic units for the protein formation. It is the only sul-fur-containing variety in indispensable amino acids. Its addition into feed can promote the growth of livestock and poultry, increase the amount of lean meat and shorten the feeing cycle. The nutrition of 1kg methionine in animal feed is equal to 50kg fish powder and the usual addition amount is 0.05 - 0. 2%. As the excess fishing and the dis-charge of sewage and industrial wastes into seas and oceans in the world in recent years have caused a quick reduc- Methionine is one of the basic units for the protein formation. It is the only sul-fur-containing variety in indispensable amino acids. Its addition into feed can promote the growth of livestock and poultry, increase the amount of lean meat and shorten the feeing cycle. The nutrition of 1kg methionine in animal feed is equal to 50kg fish powder and the usual addition amount is 0.05 - 0.2%. As the excess fishing and the dis-charge of sewage and industrial wastes into seas and oceans in the world in recent years have caused a quick reduc-