Abstract: Objective To study the killing effect of soy and vinegar on Trichinella spiralis muscle larvae.Methods The viability of Trichicnella spiralis muscle larvae after treated with vinegar or soy in vitro was determined by methy lene blue-eosin-borax(MEB)staining.Forty-emght male Kunming mice were randomly divided into 3 groups.Each group of mice was orally inoculated with 300 muscle larvae treated with vinegar or soy,respectively.All infected an imals were slaug htered at 42 days post-infection.The muscle larvae were collected and their reproductive capacity index(RCI)were calculated.Results The mortality of muscle larvae treated with vinegar for 3,6,12 and 24 hr was 0.99%,2.94%,24.53% and 100%,respectively.The mortality of the larvae treated with soy for 24,48,72,96,120,144,168,192,216 and 240 hr was 0.98%,2.86%,3.06%,4.81%,5.50%,9.35%,10.42%,11.43%,12.50% and 13.59%,respectively.The larval mortality increased a long with the vinegar or soytreatment tmie(P<0.05).The results showed that the RCI(4.07)of the larvae treated with vinegar for 3 hr was significantly lower than that of the fresh larvae(RCI=178.10,P<0.05).The RCI of larvae treated with vinegar for 6 hr was 0.The RCI of the larvae treated with soy for 12,24,36 and 48 hr was 13.78,10.94,1.00 and 0.The RCI decreased a long with the vnegar or soytreatment time(P<0.05).Conclusion Trichinella spiralis muscle larvae lost the infectivity comple tely after treating with vinegar for 6 hr or with soy for 48 hr.