The authors present a numerical investigation on the performance of corrugated-sheets-stacked heat and moisture exchanger (HMX) applied to counter-flow dew point air cooler. The computational simulation software for this investigation was developed under Engineering Equation Solver (EES) environment. The results showed that the HMX could run with stably high effectiveness (generally, wet bulb effectiveness over 130% and dew point effectiveness over 85%) and supply product air at stably low temperature, as well as improve automatically the total cooling capacity with the temperature rise of the ambient air. The HMX also presented high adaptability to the various climate conditions in Southern Europe, Northern Europe and the UK. The renovation in heat exchanger configuration could lead to significant increase in the cooling capacity and COP for dew point coolers, and decrease in size and cost of the coolers at the same cooling output. The major factor affecting the cooling performance was the relative humidity of inlet air, therefore the HMX was particularly suitable for heat-intensive places in winter, i.e. computer data centres. The optimized air-channel’s geometric sizes of height and length were 0.005m and 1.0m respectively. The ideal range of operational conditions of working air ratio should be between 0.3 and 0.5 and the reasonable velocity of inlet air around 1m/s, while the inlet water temperature had little effect on the performance.