Cardiac resynchronization therapy (CRT) is one of the most important non-pharmaceutical therapies for chronic heart failure. However,30% patients have poor or nonresponse to CRT. In this paper,we reviewed some main factors influencing the benefit of CRT. And the optimized strategies to improve the efficacy of cardiac resynchronization therapy were also reviewed,including indication,left ventricular pacing site,device programming,medicine and new pacing mode.