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The objective of the research is to investigate the hysteretic behaviour of beam-to-upright connections commonly used in cold-formed steel storage racks, and their role in predicting the structural response of steel storage racks under seismic action. The mechanical beam-to-upright connections are commonly utilised for their convenience in assembly and adjustment. Steel storage racks are slender structures which are sensitive to the second-order effect. The static and dynamic performance of rack structures are thus significantly influenced by the behaviour of connections. Due to the complex nature, current design of beam-to-upright connections largely depends on experiments which are comparatively expensive and time-consuming. To overcome the disadvantages of conducting experiments, this study apply the Component Method to predict the flexural behaviour of beam-to-upright connections in terms of the rotational stiffness and the load-displacement behaviour of main deformable components. Another knowledge gap in research of rack structures is the cyclic behaviour of connections. Cyclic tests on two widely used connection types are carried out considering different geometric details. The deformation characteristic and moment-rotation relationships of test specimens are recorded in the experiments. Moreover, based on experimental and analytical results, Pinching4 model is employed to characterise the hysteretic behaviour of the connections, and the corresponding model parameters are proposed. Furthermore, finite element models of connections incorporating fracture simulations are established and verified against the experimental results. Parametric studies are conducted to determine the effects of various parameters. Taking advantage of the finite element analysis software, the proposed hysteretic model of connections is applied in the dynamic analysis of rack structures to improve the accuracy of transient dynamic analysis of racks under seismic loading.