Abstract: The development history and current status of monitoring of slope deformation techniques in open pit mines are reviewed.Based on the practice of shuichang open pit mine,GPS slope displacement monitoring system is set up,including fixing datum mark and monitoring mark,laying out of GPS baseline vector network,determining the ways and periods of monitoring,etc.It is proved that GPS could meet the needs of slope deformation monitoring in open pit mines completely,and the monitoring system is successful and infective by practice.