The invention belongs to the technical field of model training, and discloses a machine learning model training method and system for a large-scale machine learning system. The machine learning model training system for the large-scale machine learning system comprises a data acquisition module, a data preprocessing module, a parameter range determination module, a central control module, a model training module, a model test module, a model evaluation module, a model optimization module, a data storage module and an update display module. The training sample set is processed through the data preprocessing module, the feature subsets of the training sample set are obtained, and the model training data volume is reduced; the machine learning model is trained based on incremental learning, so that the accuracy of model training can be improved; the optimal parameter value is determined in the value range of each parameter through the model evaluation module and the model optimization module, and the model parameters are adjusted, so that the training efficiency of the model in machine learning is improved.