Climate is the basis for building energy simulation.The global warming will cause the change of building energy demand.Based on the historical observation data over 30years in Xi'an,the paper got the recent-term,midterm and far-term hourly meteorological data of the typical meteorological year in Xi'an by choosing recent prediction of SRES A1Bof Inter-governmental Panel on Climate Change(IPCC)and using a statistical downscaling method-Morphing.The office,residential,hotel and store buildings were simulated to predict the different building HVAC load.Result shows that the climate change in terms of global warming would lead to less energy use for winter heating and more for cooling during the summer months.The heating/cooling loads could guide the choice of the equipment and control,so it could have important implications for nationwide energy and environmental policy for the building environment.