Water is the essential thermal media for cooling equipment, central air-conditioning, boilers and others to cool or store energy, but the storage of water in the system for a long time will cause not only the growth of bacteria and algae, but also the corrosion of the equipment surface. It was reported that electromagnetic water treatment would kill bacteria and algae, remove dirt and inhibit metal corrosion. In this paper, an experiment platform composed by stainless steel sink, electromagnetic water equipment, filter column, circulating pump is used to evaluate the effect of electromagnetic water treatment on the water environment and metal equipment, by tracking the contents of calcium carbonate and dissolved oxygen in the water under the action of the electromagnetic treatment, and analyzing the chemical composition of the sediment in the filter column produced in this process. The experiment results show that the electromagnetic water treatment has the sterilization function, but it also promotes the corrosion of the surface of metal equipment.