With the development of the medical training systems and surgical simulation techniques, the improvement of deformable soft tissue simulation becomes highly demanded. Realtime performance of simulation algorithm is the most urgent bottleneck problem that needs to solve. This paper introduces a solution to implement deformable simulation of biological soft tissue in real time. This is accomplished through the use ofhierarchical position based dynamics, implemented usingCUDA parallel framework. The simulation results are directly sent to vertex buffer objectfor rendering to avoid the costly communication between CPU and GPU. The experimental results show significate improvements on performance in comparison to CPU algorithm.