In recent years, NVIDIA proposed a developing platform for GPGPU. They also extended C language to parallel computing language, CUDA. In the meanwhile, the growth of memory capacity inside a computer enhances the feasibility of memory based database. In this paper, a memory database was proposed based on GPU memory. This study focus on how GPU can improve common operations for rational databases. Some comparison between proposed database and SQLite were also mentioned. The experiment result shows that GPU based database has better performance than SQLite. This research suggests a better solution to improve the performance of memory database using GPU.