A method of producing silk or silk-like protein wherein silk or a silk-like polymer comprising at least one protein selected from among domestic silkworm fibroin, wild silkworm fibroin, elastin and fibronectin, and essentially comprising the aforesaid domesticated silkworm fibroin or silkworm fibroin is designed. The minimum unit of the silk or the thus designed polymer is synthesized, and the polymer of the minimum unit thus synthesized is integrated into at least one expression vector selected from among expression vectors containing T7 promoter. Then, the expression vector is integrated into E. coli BL21 (DE3) pLysS or BLR(DE3) pLysS, and the E. coli is grown in a medium selected from among composite media.