[en] Reviewed are the most substantial results of studies on development of analytical (mainly destructive) methods determining the burnup depth in irradiated nuclear fuel. It is shown that the burnup value is found on the basis of data on chemical and physical analyses of irradiated fuel. The following methods are used for this purpose: measurement of the decrease of the total number of heavy element atoms in the fuel as a result of irradiation; measurement of values of selected ratios of heavy isotopes before and after the fuel irradiation using equations with corresponding nuclear constants; measurement of values of selected ratios of heavy isotopes before and after irradiation relative to their yield at the fission of heavy-isotope nuclei. The ion-exchange and extraction-chromatographic methods are analyzed from the point of view of their application to measuring the burnup depth of nuclear fuel. Described in detail are the methods of separation of such elements as lanthanides, uranium, cesium, europium, ruthenium. While performing quantitative estimates, the most effective results may be obtained using the mass-spectrometric, coulometric, X-ray spectral and gamma-spectral methods