In allusion to waste and irregularity emissions of the condensate water of split air-conditioner,with the actual energy saving potential to recycle the condensate water use for precool the inlet air of condenser, the author by means of make a device to recycle and precool the condensate water, then apply this device to split air-conditioner of a laboratory, and experiments are conducted. The computation and analysis results showed that before and after equipped with the precooled device, COP of the conditioner increasing 12.94% and 9.52% respectively under the conditions which applying sufficient cold water or produced condensate water by itself. Meanwhile, a certain gap of quantity between the produced condensate water and the cool water demanded was discovered, the former only account to 56.26% of the latter. In the end, combine the experiment condition and results to give some corresponding suggestions so as to the application and popularization of the precooled device.