Abstract: Objective To identify and evaluate the potential communicable disease risk during 2010 Shanghai Expo in Songjiang district in Shanghai and provide baseline data and evidence for the development of the emergency response preparedness plan and public health protocol. Methods The identification and evaluation of potential communicable disease risk during Shanghai Expo was conducted by using by Delphi method, then the potential risk of 10 communicable diseases were calculated by using the formula P(Risk)=L(likelyhood)*I(impact)*V(vulnerability). Results Among 10 communicable diseases, the risk of influenza was highest with the P value of 19.73, followed by infectious diarrhea (P value=14.40,) measles, cholera, hand foot and mouth disease, common cold, hepatitis A, dysentery, gonorrhea and acute hemorrhagic conjunctivitis. Conclusion The public health safety during Shanghai Expo would depend on the close multi sectoral cooperation. The study result provided evidence for the development of public health preparedness plan and public health protocol during Shanghai Expo.