The invention provides a magnetic 
resonance image 
feature extraction and classification method based on 
deep learning, comprising: S1, taking a magnetic 
resonance image, and performing pretreatment operation and 
feature mapping operation on the magnetic 
resonance image; S2, constructing a multilayer 
convolutional neural network including an input layer, a plurality of convolutional 
layers, at least one 
pooling layer / lower sampling layer and a fully connected layer, wherein the convolutional 
layers and the 
pooling layer / lower sampling layer are successively alternatively arranged between the input layer and the fully connected layer, and the convolutional 
layers are one more than the 
pooling layer / lower sampling layer; S3, employing the multilayer 
convolutional neural network constructed in Step 2 to extract features of the magnetic resonance image; and S4, inputting feature vectors outputted in Step 3 into a Softmax classifier, and determining the 
disease attribute of the magnetic resonance image. The magnetic resonance image 
feature extraction and classification method can automatically obtain highly distinguishable features / feature combinations based on the nonlinear mapping of the multilayer 
convolutional neural network, and continuously optimize a 
network structure to obtain better classification effects.