The theme of this paper is to design and implement the software for the RFID parking control system which uses the advantage of the long range RFID without an internal power source. At first, we introduce the hardware system of PUR3000 reader which is part of our parking control system, then we describe the principle of the system and the concern about the design to fulfill the functional needs. The whole system is divided into 4 modules. The reader module will communicate with PUR3000 reader through a standard serial port, using its application interface to detect and read the identification of the RFID tags. The database module provides add, delete and update operation of the information master data to the control module by directly accessing the data file. The control module manipulate the reader module and the database module to provide the system function required such as register and identify of the car. The GUI module provides a easy way for the system administrator to setup and operate the parking control system. The GUI module is beyond the scope of this paper. We will give the detailed design and implementation for the other 3 modules case by case regarding to the requirements of the system functionality. All the works are implemented through Visual Studio 2005 on Windows platform.