In order to improve the fatigue performance of orthotropic steel deck, a new type of wave plate-UHPC composite bridge deck structure with full curvilinear section was proposed. The influence of each design parameter of section on the mechanical properties of the structure was studied. The response surface method was used to optimize the design parameters, and the fatigue performance of the optimized structure was carried out. The research results show that the transverse projection length, longitudinal projection length and curve degree are important structural design parameters that affect the mechanical properties of the structure. The self weight and stiffness of the structure will be significantly increased, induced by the increase of longitudinal projection length. And the level of stress concentration at the bending position can be enhanced by the increase of curve degree. The regression model established by response surface method has a high fitting precision. The error between the experimental value and the predicted value by response surface method is 0.236%, and the optimized design parameters are satisfactory. Compared with the traditional orthotropic plate, the fatigue performance of the optimized composite deck structure is significantly improved, the fatigue life at the weld toe of the roof plate is increased by 4.9 times, and the fatigue life of the weld toe of the diaphragm plate is considered as nearly infinite.