The purpose of the study was to compare two methods for destruction of biological material for selenium (Se) analysis: wet digestion by conductive heating in programmed digestion block and digestion in microwave oven. In both methods samples were prepared in a closed system using nitric acid. Selenium was analysed by electrothermal atomic absorption spectrometry. The results have shown that both methods are convenient for complete mineralisation and are accurate in determining selenium in a variety of foodstuffs. Microwave digestion, however, has the advantage of speed and simplicity over the conventional heating procedure.