Abstract:The accurate prediction of slope stability is of great significance for reducing the risk of slope instability. To achieve efficient and accurate slope stability prediction, this study proposed a slope stability prediction model based on particle swarm optimization (PSO) for light gradient boosting machine (LightGBM), namely the PSO-LightGBM model. This model first used the PSO algorithm to optimize key parameters of the LightGBM model, reducing the impact of parameters of the LightGBM model in practical engineering applications. Then, the optimized LightGBM model was adopted to classify and predict the slope stability. K-nearest neighbor (KNN), support vector machine (SVM), LightGBM, grid search-optimized LightGBM (GS-LightGBM), and genetic algorithm-optimized LightGBM (GA-LightGBM) were selected as comparison models. Accuracy, precision, recall, and F1 score were used as evaluation indicators for the predictive performance of each model, and the classification results of each model were visualized through the confusion matrices. Based on the feature importance analysis of the PSO-LightGBM model, the relative importance of each factor in slope stability prediction was quantified. The results showed that the PSO-LightGBM model significantly outperformed all other comparison models across all evaluation indicators on the test set, demonstrating strong classification prediction performance and generalization ability. Through feature importance analysis, the factors affecting slope stability were ranked in descending order as follows: slope angle, slope height, cohesion, internal friction angle, soil unit weight, and pore water pressure. This study provides a new method for the accurate prediction of slope stability and offers an important reference for the safety design and risk assessment of slope engineering.