Abstract: This paper discusseshow to use HLLC method to treat moving boundary. The explicit finite volume method based onunstructured meshes is employed to solve Eulerian equations. Theimpulse piston moving backward and forward is simulated tovalidate the moving boundary treatment. As an example, flows around a staticcylinder and around a moving cylinder in a static flow field arecalculated. The numerical results indicate that it is feasible to use theHLLC method to treat the moving boundary condition.