介绍并讨论了一种逻辑加密卡安全体系实现的设计方法，针对加密卡成本较低、使用方便、安全性较好、用途广泛等要求，提出了包括密码认证体系和写保护体系在内的安全系统，给出了密码认证过程的几种模拟结果 This paper introduces and discusses a design method of security system of logic encryption card. Aiming at the requirements of encryption card, such as low cost, easy to use, good security and wide range of uses, the paper puts forward the security including password authentication system and write protection system System, gives several simulation results of the password authentication process