A technique has been elaborated for preparation of deuterated membranes from deuterated cells of Micrococcus lysodeikticus containing 85--90% of deuterium according to the data of IR and PMR spectroscopy. Normal lysis of the deuterated cells of M. lysodeikticus requires a concentration of lysozyme which is eight times higher than for usual cells (8 mg per 1 g of wet deuterated cells) and an addition of the lytic enzymes E-2 (2 mg per 1 g of wet deuterated cells). Preparations of deuterated membranes purified from ribosomes and proteins can be obtained by treating of the lysate with RNAase and washing in 0.5 M NaCl. The purity of the deuterated membranes was evaluated by the evidence of electron microscopy, IR spectra and enzyme activities. After hydrogen atoms were substituted by deuterium, the secondary structure of the total membrane protein, the ratio between the activities of the respiratory chain enzymes, and the relative content of the lipid and protein components of the deuterated membranes remain at the same level as in the protonated ones.