The moisture movement and heat transfer are highly coupled within building materials. The correct evaluation of these phenomena is important for accurately predicting the heat and moisture flows for thermal performance and building energy consumption analysis. In order to analyze the effect of moisture levels on a drying building energy performance, the heat and moisture coupling transfer of building envelope with multilayer composition in the cold serious area Harbin, China was simulated. The freezing of liquid moisture in exterior envelope was considered. It is concluded that the moisture performance changes during initial drying often account for a significant fraction of the overall load and have notable effect on the building energy consumption. The energy consumption of the new building was significantly high in the first few years, especially in the first year. The energy consumption in the first year is 4.0% higher for the modeled room and 11.6% higher for the analyzed envelope as compared with that of the tenth year.