High-performance parallel computing has always been an important scientific issue in the study on climate system models. However, with the development of computer technology, computer architecture is becoming more and more complicated while the complexity of the climate system has made it a challenge to develop high-performance climate system models. This paper adopted a completely new parallel programming method. Based on the programming framework J-Earth, a high-performance parallel general circulation model, H-GAMIL, was developed. With detailed analysis and deconstruction of the original GAMIL model, the characteristics of J-Earth was combined with GAMIL to reconstruct the H-GAMIL in this paper by using the object-oriented programming method. The reconstructed H-GAMIL possesses the features of standardization and modularization of modern software and also has new functions of automatic 2D subdivision, hybrid parallel implementation of MPI (Message Passing Interface) and OpenMP (Open MultiProcessing), as well as parallel output, thus solving the problem that the one-dimensional subdivision of the original model was subjected to the restriction of the processor and the serial IO problem in the original model. Based on the above work, in the present study we conducted a parallel efficiency test on the H-GAMIL. The result shows that when the model's horizontal resolution was 1°×1°, hundreds of processors could be used and the parallel efficiency could reach above 40%, and the load balance totaled more than 70%. The test result suggests that the H-GAMIL possesses a relatively high parallel efficiency and scalability. Meanwhile, a comparative analysis of the simulation performance of H-GAMIL was conducted in this study. The result shows that the H-GAMIL maintains the conservativeness of the original model and has the same simulation performance as the original one. Thus it meets the computing requirements for climate study and can be applied for practical use.