With the development of building technology and techniques,more and more new types of large-span roof structures comes out,they are light,flexible and colorful.Many new space structures are being developed by means of using new materials and technologies.And Shanghai South Railway Station being built is one of these new structures.But large-span structures have the characteristics of low gravity,large flexibility and low damp.Wind load is the key to structure design.Results are acquired by wind tunnel test on model of Shanghai South Railway Station,and analysis with the ANSYS,The tests results can be used as references for roof structure design,and the production of Shanghai South Railway Station built is being achieved.