Two mulberry varieties Morus alba var. Kokuso-27 and Morus indica var. Kanva-2 were compared with Morus alba var. Balady (native) in their effects on the protein banding patterns of 5th-instar larvae of Bombyx mori. There was an obvious variation in the number and position of the bands, with many bands specific to a particular treatment. Protein of larvae fed on Kokuso-27 was characterized by the presence of 29 and 10 KDa bands; Kanva-2 produced bands at 251, 74 and 8 KDa; and Balady was characterized by bands at 38 and 11 KDa. When Kokuso-27 was enriched with vitamins C or B, or any of three kinds of bee-honey (clover, cotton and citrus honey) at various concentrations, new protein bands appeared relative to controls. Vitamin C produced bands at 56 and 43 KDa; protein bands at 290, 35 and 7 KDa were present in the control but absent in vitamin B treatments. Feeding with clover honey showed characteristic bands at 303, 49, 44, 37 and 21 KDa which were absent in the control. Cotton honey produced characteristic bands with molecular weights of 160, 52 and 13 KDa. Citrus honey produced bands at 73, 33, 29 and 8 KDa. Keywords: Morus alba var. Kokuso-27, Morus indica var. Kanva-2, Morus alba native, vitamin C, vitamin B, bee-honey, SDS-PAGE. Egyptian Journal of Biology Vol. 10 2008: pp. 11-1