H2O2 and CH3COOH were used to degrade chitosan(CTS), several CTS samples with different molecular mass were obtained, including 380000, 200000, 144000, 92 000, 72000, 32000, 11000, and 4000. These CTS samples were respectively used to treat cotton fabric together with butanetetracarboxylic acid (BTCA). Wrinkle recovery angle(WRA), Tearing strength rate(TSR), whiteness index(WI) and antibacterial rate of S.aureus of the composite finished fabrics were tested. Effect of CTS molecular mass and concentration on the anti-winkle and antibacterial properties were discussed. The results show that the WRA of cotton fabric is 264.0 °, warp TSR is 77.3 %, weft TSR is 63.5 %, WI is 68.3 and antibacterial rate of S.aureus is 68.7 %, which treated with CTS(molecular mass 200000, 1.0 g?L-1) and BTCA by one-bath process. When 10.0 g?L-1 antibacterial agent AGP was used together with CTS and BTCA, the antibacterial rate of finished cotton fabric is 98.5 %, WRA is 263.0 °, warp TSR is 83.5 %, weft TSR is 76.4 %,and WI is 69.1.