Hemolymph origin silk gland protein (HOSGP) was identified from the silk gland of wax moth, Galleria mellonella and characterized using antibodies against larval hemolymph protein and silk gland. Hemolymph and silk gland extracts were electrophoresed and western-blotted with each developmental stage. HOSGPs were present in the silk gland. To confirm the presence of HOSGP in other tissues, western-blotting was performed with extracts of Malpighian tubule, midgut and fat body. HOSGP was also present in the fat body. HOSGP was pre-sent in large amounts in the silk gland of the last instar larvae and wandering stages when silk is actively produced. HOSGP was partially purified by KBr density gradient ultracentrifugation and prep-cell, and characterized.