In order to realize damage warning of complex steel structures under environmental conditions, SVR-ARMA combinatorial model based on particle swarm optimization (PSO) is proposed.The damage warning method of complex steel structure is established by mean control chart and the proposed model. The accuracy of the prediction model is verified by the monitoring data of the White-wave River Ferris wheel inWeifang city.The results show that compared with the SVR model, SVR-ARMA model and PSO-SVR model, the PSO-SVR-ARMA model has higher generalization ability and prediction accuracy.In the structural damagewarning, the PSO-SVR-ARMA model can detect the slight abnormal changes of the modal frequency caused by the damage, which greatly improves the accuracy of the damage warning. The results can provide reference for damage warning of complex steel structures under environmental conditions.