Reliability index is the basic element in the reliability design for a product. On the oasis of the analysis about security, functional reliability and storage reliability in fuze system, the evaluated methods for reliability index in fuze system are discussed and the new points of view have, been approved. So far the most commonly used method to evaluate the functional reliability of the fuze is founded in MIL-1316E "The principles for the Design of Fuze security", fuze system hazard analysis and detailed analysis, such as fault tree analysis, shall be conducted to arrive at a estimate of the safety system failure rate to identify and single-point. or credible failure modes. All of these have an important reference value for improving the reliability design and experimental level about fuze system.