Abstract: In order to improve the preservation time of Tongbai Doujin and develop a special fresh-keeping agent based on natural spices, the bacteriostatic ability of spice extracts on Tongbai Doujin was studied in this paper. Diameter of inhibition zone was used as index. Effects of spice types, extraction solvents, liquid-solid ratio, extraction temperature and extraction time on the antibacterial effect of spice extact on Tongbai Doujin were studied. The extraction conditions were optimized by orthogonal method. The results showed that among nine spices selected, anise, pepper and clove had obvoius antibacterial abilities. The optimum extraction conditions are shown as follows: the extraction solvent was 75% ethanol and the liquid-to-solid ratio was 10∶1 (mL/g). The extractions for star anise, pepper and clove were conducted at the extraction temperatures of 90 ℃ for 2.0 h, 90 ℃ for 2.5 h and 70 ℃ for 2.0 h, respectively. Under these conditions, the diameters of inhibition zone for star anise, pepper and clove were 19.6 mm, 20.7 mm and 20.4 mm, respectively. The preservation time of wet Tongbai Doujin by star anise, clove and pepper, respectively were 8 d, 9 d and 9 d at 25 ℃, 3 d, 4 d and 4 d at 37 ℃, 4 d, 5 d and 5 d at 45 ℃. Results indicated that natural spices have good preservation and fresh-keeping effects on wet Tongbai Doujin.