The fire resistance of the construction materials is traditionally measured by the fire resistance test method in accordance with the international standards, i.e. ISO 834-1, BS476-20, and ASTM E119, etc. In fire resistance door test, a full-scale test door is fitted into a standardized furnace for testing and then the test report is issued to ensure how long the door can resist the fire. A single leaf wooden door was tested in this study. During the 1-hour test, the temperatures inside the furnace and six measured points on the unexposed surface were recorded with the thermocouples. COMSOL Multiphysics®, was used to develop a three- dimensional heat transfer model for the fire door under the fire resistance test. In results, it showed that the curve trends of the simulated unexposed temperature of the six measured points (three thermocouples place on the door frame and three thermocouples place on the door) generally agreed with the experimental data. For the door leaf, the maximum temperature error between the experimental data and the simulated data was within ± 25%. For the door frame, the maximum temperature error between the experimental data and the simulated data was within ± 35%. The larger difference on the door frame was calculated because the practical smoke passing through the door crevice between the leaf and frame, due to the door sealant failure, was not simulated in this model.