Wind tunnel tests and analyses of the response of the Seo Hae Grand Bridge were conducted using full aerorelastic model technique. A 1/250 scale aeroelastic model were used to measure the responses of the prototype bridge at the twelve critical locations. Two different turbulent intensity values simulating open and turbulent exposure conditions were used to conduct the testings. In order to confirm the model design and fabrication, natural frequencies measured from the model were compared with those from the analysis. Comparisons of the response from the tests were made between the full aeroelastic model and the section model. Tests for two construction stages such as a concrete single pylon and cirtical double cantilever stage with and without tie-down cable were also conducted and the results were compared.