Many surgical simulators use mesh method to deform CG models such as organs and blood vessels because the method can easily calculate the deformation of models; however, it has to split and reconstruct the mesh of the models when the model is broken such as bleeding. On the other hand, particle methods consider a continuous body such as solid and liquid as a set of particles and do not have to construct the mesh. Therefore, in this paper, we describe how to simulate bloodstream by using MPS (Moving Particle Semi-implicit) method that is one of particle ones. In the simulation, we use the aorta model as the blood vessel model, and the model is constructed with particles. As the result of the simulation, it took 20ms to deform the blood vessel and to simulate bleeding with the model that is constructed with 15,880 particles for the blood vessel and 6,688 particles for the blood.