Abstract: Track Quality Index(TQI) is an important indicator reflecting the overall quality status of the high-speed railway, thus the analysis of the change pattern of TQI data can provide important guidance and reference for the maintenance and repair of high-speed railway. This paper proposed a 3D convolutional neural network model with multiple feature data, analyzed the characteristics of TQI data, extracting time, space and detection items to form a three-dimensional feature data set. Based on 3D convolution neural network algorithm, the paper constructed an 8-layer TQI prediction model, and optimized the model from the aspects of initialization parameters, learning rate, activation function, loss function, Dropout method, and used the detection data of a high-speed railway line for experimental verification. The test results show that the 3D convolution neural network model can better predict the state change trend of high-speed railway lines. Compared with BP neural network and 2D convolution neural network, the average absolute error is reduced by 41.48% and 26.32%, and the mean square error is reduced by 65.42% and 39.93%, respectively. It is proved that the method is accurate and effective, and has practical value for predicting TQI and formulating maintenance plan of high-speed railway lines.