Nowadays, it is necessary to pay attention to correctly determination of actual fire resistance of concrete construction and to establishment the possibility of construction further maintenance after the fire. Measure fire resistance of building construction can be performed by experimental methods as well as calculation methods. In the paper, a definition of fire resistance is given, all the basic ways of its determination are listed, the methods of testing to assess the fire resistance corresponding to all the requirements of modern Russian and American requirements are considered, the main similarities and important differences are identified. The general approach in both countries is the same, but there are differences in methodology and constants. Fundamental difference is in design standards due to the fire resistance, from what follows that in the US the focus is on a specific value for the corresponding fire resistance of building structures and only by the desired value their minimum sizes is determined, in Russia, in contrast, the priority is appointment of structure, with which the required fire resistance is determined. With regard to testing, it is possible to allocate the characteristic differences in the number of thermocouples to measure the temperature in the furnace, and on the unexposed surface, in size of the test samples, which affects the accuracy of results and measurements. In addition, the difference in the temperature range of the furnace can be shown, which may indicate that the resulting fire resistance of the same sample with one standard will not coincide with the corresponding one tested with other standard. It should be noted that the requirements for the fire resistance of certain structures by US standards are described in the test methods, but in the computational method, such requirements are not specified. To all other, according to ASTM samples may be tested using hose stream.