To improve the efficiency of the review simulation model of the bridge monitoring unit and study the influence of different parameters of the single-tower mixed beam cable-stayed bridge on the bridge ’s completed state in the construction process，this paper，taking the cable-stayed bridge of Tongji Road in Foshan with a span of （200+68+46） m as the engineering background，adopted the single control variable method and response surface-Monte Carlo method for sensitivity analysis.Taking the main beam alignment，main tower alignment，main beam stress，and the variation of cable-stayed bridge force as control objectives，this paper studied the influence of the variation of main beam weight，initial tensile force，and other parameters on the state of the completed bridge.The results show that the dead weight of the main beam and the initial tensile force are sensitive parameters.Construction temporary load is a sensitive parameter，and girder stiffness and cable elastic modulus are non-sensitive parameters.