In this paper, the RFID based modular clerk management system in cloud is proposed to provide the modular clerk management to different companies individually with less implementation cost. The management procedures for clerk are modular and can be adopted by the system manager individually. All the clerks are given an individual RFID tag for the induction. By managing the priority recorded in the database in cloud, the gate access management, the attendance state of clerks and even the salary for clerks can be automatically arranged. Based on cloud, different companies can access the management system and database in virtual machines. In addition, the modular management system can be used according to the on demand requirements of companies. The modular system only needs to be established once and repeatedly used for individual companies.