The invention discloses a frozen fresh pomfret freshness rapid grading method based on deep learning, which belongs to the technical field of refrigerated food quality evaluation. Specifically, freshness grading is carried out on a pomfret image based on a Mask R-CNN technology, a frozen fresh pomfret image is obtained, a digital image data set is established, feature learning is fused into the process of establishing the model, accurate detection and segmentation are carried out on fisheye and gill parts, feature learning can be carried out autonomously, and the freshness of the pomfret can be accurately segmented and classified. Therefore, quick detection and intelligent prediction of the quality deterioration of the frozen fresh pomfret are realized; and the expandability and mobility of the model are improved. A rapid, low-cost, accurate, nondestructive and real-time automatic detection technology is realized, and the health and benefits of consumers are guaranteed. Product qualityis controlled for different varieties of cold chain storage and transportation environments and supply chain sources, and technical support is provided for public health and epidemic prevention.