In order to ensure the structural safety of the cable-stayed bridge for hybrid beams of unilateral asymmetry with semi-floating system, a sea-crossing cable-stayed bridge in Fujian Province is taken as the background, the dead load cable force and cable force increment of cable-stayed cables after bridge formation are tested by vibration frequency method. The results show that the longitudinal distribution law of the measured cable force under dead load is consistent with the theoretical value, and the deviation between the measured value and the theoretical value is basically within 5%. The cable force on both sides of the main tower is evenly distributed, and the upstream and downstream cable forces are symmetrically distributed. By comparing with the bilaterally symmetrical cable-stayed bridge, it has been confirmed that the three adjustment processes of the cables can effectively overcome the effects of structural asymmetry (the difference in span length is 90 m), and there are significant differences in the weight and stiffness of the main beam), thus meeting the requirements for cable force control. Under the four working conditions of the static load test, the check coefficient of cable force increment is 0.82-0.93 and the cable-cable force increment has a strong linear relationship with the loading efficiency, indicating that the deformation of cable-stayed cable conforms to the elastic characteristics. The actual bearing capacity of the structure meets the design requirements, which verifies the feasibility of the bridge design concept and provides a technical reference for the construction of asymmetric hybrid cable-stayed bridge.