Abstract: Wool fabrics were pretreated with proteases, followed by zirconium flame retardant finishing. The enhancement of flame-retardant effect of wool via Savinase pretreatment was studied and the performance of finished wool fabrics was determined. Compared with FT-IR of the fabrics before and after flame-retardant finishing, scanning electron microscopy (SEM) analysis of the ignition residues and thermogravimetric analysis, it was confirmed that Savinase protease pretreatment of wool can destroy the surface structure to some extent, and facilitate the adsorption of flame retardants onto wool fibers. Enzymatic pretreatment efficiently decreased the char length of flam-retardant finished fabrics after vertical burning, and increased 5.6 percent of the limiting oxygen index (LOI). These results showed that protease pretreatment further improve the flame-reatardant effect of wool fabrics. improve the flame retardance of wool.