By optimizing the scheme of EinsteinPodolsky-Rsoen(EPR) by spontaneous parametric down-conversion and using the technique of coincidence counting and post selection,the high fidelity polarization EPR entangled state has been prepared.The results show that the fidelity of EPR entangled state approach as almost 0.99,and the coincidence rate can be more than 3 500 Hz.It overcomes the limit that the fidelity and intensity of entanged state can′t increase synchronously.A stationary entangle source is...