Abstract: The shear lag effect significantly impacts the load-bearing performances of cable-stayed bridge structures, making its accurate calculation and analysis both theoretically and practically valuable in engineering. This study reviews the innovation process of research methods for shear lag effect in bridge structures from four aspects: analytical analysis, experimental study, in-situ testing, and numerical simulation. By integrating recent advancements in calculating effective width coefficients for cable-stayed bridge girders, the existing problems and solutions in the research on the shear lag of cable-stayed bridges are pointed out. The application efficacy of the energy variational method in shear lag analysis is systematically summarized, while the engineering practicality of the finite segment method and additional deflection method is evaluated. Case studies are employed to assess shear lag effects under dead and live loads during construction and operational stages, alongside a review of current methods for determining effective width coefficients. The research shows that: in analytical analysis, the energy variation method and the finite segment method can be used to analyze the shear lag effect of the main girder of cable-stayed bridges, but the internal force values of the beam elements need to be known; compared with traditional methods, the additional deflection method can more accurately calculate the shear lag effect near the zero-moment section of the main girder; further research should be conducted on the impact of material performance deterioration, of distortion, and of temperature effects on the shear lag in cable-stayed bridges, and beam element models that consider the shear lag effect should be developed.