In order to solve the summer-spending problem of direct air-cooling unit, the plate evaporative condensing technique was proposed to shunt turbine exhaust steam partly and reduce the air cooling condenser (ACC) heat load, thus the unit operating back-pressure decreases and the output increases.The plate evaporative condenser system was operated in a Direct Aircooling Unit and the operating characteristic was obtained.The results show that operating efficiency increases with the increase of environmental temperature.With the increase of environmental air humidity, the steam flow and supplement circulating water flow both decrease and similar trends are observed.However, when the air humidity reaches a specified value, the steam flow and supplement circulating water flow trend to be a definite value.