The invention provides an MRI (
Magnetic Resonance Imaging) 
brain tumor localization and intratumoral segmentation method based on a deep cascaded 
convolution network, which comprises the steps of building a deep cascaded 
convolution network segmentation model; performing model training and parameter optimization; and carrying out fast localization and intratumoral segmentation on a multi-
modal MRIbrain tumor. According to the 
MRI brain tumor localization and intratumoral segmentation method provided by the invention based on the deep cascaded 
convolution network, a deep cascaded 
hybrid neuralnetwork formed by a full convolution neural network and a classified convolution neural network is constructed, the segmentation process is divided into a complete 
tumor region localization phase andan intratumoral sub-region localization phase, and hierarchical 
MRI brain tumor fast and accurate localization and intratumoral sub-region segmentation are realized. Firstly, the complete 
tumor region is localized from an 
MRI image by adopting a full convolution 
network method, and then the complete tumor is further divided into an 
edema region, a non-enhanced 
tumor region, an enhanced tumor region and a 
necrosis region by adopting an image classification method, and accurate localization for the multi-
modal MRI brain tumor and fast and 
accurate segmentation for the intratumoral sub-regions are realized.