The recycling of blood from slaughterhouses is an important issue in animal industry and investigations on this subject are being promoted. In the present study, the blood meal extracted from blood from slaughterhouses was examined for possible use as a protein source in the artificial diet for silkworms. Blood meal as a source of protein in comparison with soybean protein meal used presently in the artificial diet for the silk worms was found to be less suitable in terms of palatability and digestibility. However, the weight of the cocoon shell was larger and there was no excess corpulence of pupa. It is thus considered that blood meal is a superior source of protein, which effectively increases the quantity of cocoon shells, and it was confirmed that the use of blood meal in comparison with current protein sources and even in terms of cost per unit weight could be very economical.