The annual energy consumption of representative office buildings in Guangzhou, P. R. China, was surveyed over a three year period. Among the modern office buildings surveyed, two largescale office buildings were chosen to analyze the energy consumption features and monthly energy consumption trends. Based on the actual occupied area calculation, the total annual energy consumption of the two office buildings was 149.3 kWh/m2 and 115 kWh/m2, respectively. The airconditioning energy consumption in two office buildings accounted for 49.2% and 38.5% of the total energy consumption. The research results could be used as energy consumption subdatabases or references for largescale public buildings in Guangzhou due to the accurate survey technique and representativeness of the survey objects. In addition, energy consumption in these office buildings was compared with levels described in other studies. Energy saving methods are proposed for buildings located in hot summer/warm winter climate zones.