International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / To enhance the production management of the rod-pumped wells in the oil field, using a high performance single-chip as the processor, a field monitor system based on GPRS is researched and developed. In the paper the hardware design and software design are expatiated, the sampling frequency and determination rules for the running state are analyzed, the rational communication protocol is designed to ensure the reliable message transmission and reduce the communication fees. In the end the field monitor system is successfully implemented and verified in practice, part of data transmission result is illustrated.