To study performance of graphic processing unit (GPU) for computational fluid dynamics, simulation on interactions between shock waves and a flame interface, a typical compressible reactive flow, was carried out on CPU/GPU heterogeneous system. Several optimal strategies are taken to raise GPU code performance. Computational results and acceleration performance of GPU with different grid number were examined. It was found that computational results by parallel GPU are the same as those by traditional CPU based on MPI parallel of 8 threads. Computational times of two parallel methods linearly grow with increase of computational grid numbers. Compuational cost by GPU is less than cost by MPI. As grid number is small(1.6×10⁴), speedup ratio of 8. 6 was achieved on GPU. As grid number grows, speedup ratio decreases. However, a ratio of 5.9 still can be held on GPU when grid number is more (4.2×10⁶). Arithmetic on CPU/GPU heterogeneous system provides a good solution for large-scale computations of compressible reactive flows.