Thermal comfort is an important parameter of indoor climate, which affects office worker health and productivity, and also aids planning for energy efficient building design and operation. To provide satisfactory thermal comfort in office workplaces under hot and humid outdoor conditions, most contemporary office buildings in Vietnam are fitted with ducted air-conditioning systems. The current Vietnamese standard TCXDVN 306:2004 for indoor climate was derived from thermal comfort research conducted between the 1960s and 1980s. This standard is limited by various drawbacks, including no distinction between natural or artificial environments. In response, this 2018 research provides physical measurements and opinion surveys of current indoor climatic conditions in representative office workplaces in three regions of Vietnam: North, Central and South. The measurement results have been transformed into ET, PMV and PPD indicators, which value demonstrate the shortcomings of the TCXDVN 306:2004 standard, while providing a baseline input for updating this standard to meet the thermal comfort needs of air-conditioned office workplaces, based on the concept of probability comfort, which are integral with the ISO and the ASHRAE standard.