In this study, various energy conservation measures (ECMs) on heating, ventilating and airconditioning (HVAC) and lighting systems for a 4-storied building in subtropical (hot and humid climate)Central Queensland, Australia are evaluated using the simulation software called DesignBuilder (DB) which isbased on EnergyPlus (EP) simulation engine. Energy consumption profiles of existing systems i.e. base casescenario are analysed and simulated first then, the simulated results are verified by on-site measured data usingHobo data logger and smart meters. ECMs, namely variable air volume (VAV) systems instead of constant airvolume (CAV), photo electric dimming control system instead of general lighting, and double glazed lowemittance window instead of single glazed window are evaluated. The effect of indoor environment on theseECMs is also discussed. It has been found that the building considered in this study can save up to 26.5%energy without compromising occupancies thermal comfort by implementing the above mentioned ECMs intothe existing system.