In recent years, with the development of image processing and artificial intelligence technology, the application of medical image big data-based analysis methods to assist doctors in decision-making and solve difficult problems in clinical practice has become a research hotspot. This project intends to establish an intelligent recognition system of lung cancer based on the image data of lung cancer patients by using convolutional neural network method. Using Python as a tool, combined with the collected medical image data, the feature extraction of lung cancer image is realized by using deep learning framework, and the unknown image is recognized by clustering learning to achieve higher classification accuracy. Finally, a software is developed to assist doctors in accurate diagnosis and improve the accuracy of diagnosis.