Abstract: Shock compression is the main source of entropy changes in ICF implosions. How to realize a nearly isentropic implosion with a series of shock waves after pulse shaping will be crucial for the optimization design of ignition targets. With the ideal and realistic equtions of state, entropy and density changes of DT with a series of shock compressions are calculated. With an initial pressure of 0.1 TPa which is then proceeded to 10 TPa with three consecutive shocks, the compressibility of DT will not be affected by the corresponding entropy change. It is found that increasing the number of shocks has a small effect on entropy change and compression ratio of DT.