Abstract: Research and design on-line steel structure rainshed deformation monitoring system to solve the online monitoring problem of rainshed deformation. The vibrating-string strain sensor installed parallel to the beam axis was used to collect characteristic information including train passing loads and environmental loads to determine the stress calculation method. Through the ANSYS analysis software, the simplified mechanics models of the wind load and rain load and snow load from the top of the rainshed were acted on the nodes of the finite element model. The spatial three-dimensional model was set to analyze the force, make predictions, find the abnormalities and damage or degradation of structural response in time. The research shows that the monitoring system helps to discover the deformation and damage of steel structure canopy.