A protocol for refolding of thioredoxin-fused cysteine-rich peptides via addition of oxidized/reduced glutathione reagent directly to unfolded soluble fused protein has been developed. This procedure allows one to skip the steps of inclusion bodies purification, denaturation/disulfide reduction as well as lyophilization before oxidative folding, and thus to improve the yield of cysteine-rich peptides in their production using E. coli expression system.