This volume constitutes the refereed proceedings of the 19th International Symposium on Neural Networks, ISNN 2025, held in Zhangye, China, during August 22-24, 2025.

The 52 full papers were carefully reviewed and selected from 60 submission. They were organized in topical sections as follows: Design, Modeling and Application of AI Algorithms; Signal, Image, and Video Processing; Modeling, Analysis, and Implementation of Neural Networks; Control Systems, Robotics, and Autonomous Driving; Machine Learning Methods and Applications.