Based on the theory of planned behavior, this study tested the impact of package travellers` perception of Influenza A(H1N1) on their intention to postpone or cancel international trips. Data were conveniently collected from 570 package travellers, who participated in outbound travel program in Korea from January to February 2010. Results of a structural equation model analysis indicated that overall, the respondents` behavioral intention to postpone or cancel international travel were well explained by their level of perception on the Influenza A Results also showed that the respondents` behavioral intention on international travel was significantly influenced by their attitude and subjective norm on Influenza A. However, perceived behavior control on Influenza A was not found to have an impact on behavioral intention and actual behavior for international travel. Findings from this study suggest that the perception of Influenza is an important variable in explaining decision-making process of international tourists.