The experiment was undertaken to see the effects of Bacillus sp. on the growth performance and disease resistance to Salmonella sp. infections. The use of probiotic microbes in poultry is commonly practiced. In this study, Bacillus subtilis was tested using a total of 120 chicks of age of 1 day after hatching. The growth traits examined were body weight gain and feed conversion rate. And also, the Salmonella resistance of Bacillus subtilis was tested after the chicks were orally administered with Salmonella pullorum by gavage force injections. The result showed that Bacillus subtilis yielded a high feed efficiency, consequently increased growth rate. For the effect of Bacillus subtilis on Salmonella infection, Bacillus subtilis significantly improved the resistance to Salmonella pullorum infection. Various clinical symptoms of Salmonella infection were highly decreased by addition of Bacillus sp.