Most disinfectants, including chlorine and its derivatives, are inactivated by interactions with organic matter. Eggshell surfaces can be contaminated by organic matter such as feces or rice straws during the production process. Therefore, an agent with high efficacy in the presence of organic matter may be effective for disinfecting eggs. When ClO2 gas was used to inhibit SG inoculated onto eggshells under wet conditions, no significant difference was observed in the presence of 0% yeast extract vs. 5% yeast extract. However, the reduction in SE with 5% yeast extract was significantly different from the control. The percentage of organic matter had a greater influence on the effect of ClO2 gas on SE than on SG.