The concrete decks in wide box composite girder bridge carrying vehicle load directly are easy to failure. So the decks in approach bridge of Jiubao Bridge are designed to renewable component. Several deck removal plans were put forward based on the structure characteristics of the Jiubao bridge. Spatial finite element model of the bridge was set up and the responses of approach bridge under different removal plan were analyzed. The analysis results show that methods proposed in this paper about deck removal in local position or in whole span are feasible; however different whole span removal method affect the mechanical behavior of the approach bridge heavily.