The Low Energy Accelerator Facility(LEAF)consists of a ECR ion source,a LEBT,an RFQ,a MEBT and three terminals.The cooling water system for high-power equipments like RFQ and power supply had designed to guarantee stable operation for LEAF.A water leakage monitoring system was designed and implemented in 2018,which could pre-warning the water leakage status of the water cooling system along the beam line and the water pump house in real time to prevent equipment damage caused by water leakage accident.