Abstract: The development background, structure and main technical characteristic of a parallel ensemble numerical weather prediction system on the Shenwei massively parallel processor system are described. The system is composed of seven subsystems: preprocessing, data assimilation, ensemble initial data generation, numerical weather prediction, post-processing, product generation and visual real-time monitoring control. The singular vector is used to create initial perturbation at the T21L19 resolution and the forecast subsystem is at the T106L19 resolution. The number of ensemble members is 32.