Radio Frequency Identification(RFID)middleware is one of the key components of an RFID network system involving different types and multiple RFID readers.The existing RFID middleware products are often complicated and expensive and thus difficult for small and medium enterprises to imple ment.In this paper,a new RFID middleware scheme with a simplified Appli cation Level Events(ALE)structure is proposed and its implementation is described in detail,aiming at domestic small and medium enterprises,with focus on practicability,simplicity and usability.The proposed RFID middle ware does not employ the full ALE structure as in the EPC global system but still contains all the basic functions of a standard RFID middleware,such as the cross-application of various readers.It also features a simple and clear framework with only a few commonly used RFID readers involved in its man agement system.Its inputs and outputs are compliant with the EPC global standard so that even enterprise users with limited programming knowledge can build their own RFID middleware system according to their specific re quirements.It is expected that not only domestic small and medium enterprises but also large enterprises can benefit from this simplified RFID middleware,which has advantages of simplified system design,short develop ment cycle,low maintenance cost and flexibility in expansion over other RFID middleware.