Motor imagery electroencephalography (EEG) has been successfully used in the brain-computer interface (BCI) systems. Broad learning (BL) is an effective and efficient incremental learning algorithm with simple neural network structure. In this work, a novel EEG multi-classification method is proposed by combining with BL and common spatial pattern (CSP). Firstly, the CSP algorithm with the one-versus-the-test scheme is exploited to extract the discriminative multiclass brain patterns from raw EEG data, and then the BL algorithm is applied to the extracted features to discriminate the classes of EEG signals during different motor imagery tasks. Finally, the effectiveness of the proposed method has been verified on four-class motor imagery EEG data from BCI Competition IV Dataset 2a. Compare with other methods including ELM, HELM, DBN and SAE, the proposed method has yielded higher average classification test accuracy with less training time-consuming. The proposed method is meaningful and may have potential to apply into BCI field.