The structure of chiral N-ethyl-N-(2,3,4,6-tetra-O-acetyl-b-D-glycosyl)-thio- carbamide was determined by X-ray diffraction method. It crystallizes in the monoclinic system, space group P21 with a = 7.6560(15), b = 10.311(2), c =14.181(3) ? b =100.88(3), C17H26N2O9S, Mr = 434.46, V = 1099.3(4) ?, Z = 2, Dc = 1.312 g/cm3, F(000) = 460, m = 0.196 mm-1, R = 0.0704 and wR = 0.1655. The total independent reflections were 5098, of which 1875 were observed with I ≥2s(I). The hexopyranosyl ring adopts a chair conformation. All the ring substituents are in the equatorial positions. The acetoxylmethyl group is in the gauche-gauche conformation. The S atom is in synperiplanar conformation, while the NCNC linkage is antiperiplanar. X-ray analysis shows that the absolute configuration of the chiral carbon atom at C(1) was proved to be b-form. The 1H NMR spectra and IR are in good agreement with the result of crystallography analysis. The NH…O intermolecular hydrogen bonds link the molecules into infinite chains connected by CH…O interactions. The structure of chiral N-ethyl-N- (2,3,4,6-tetra-O-acetyl-bD-glycosyl) -thio- carbamide was determined by X-ray diffraction method. It crystallizes in the monoclinic system, space group P21 with a = 7.6560 (15), b = 10.311 (2), c = 14.181 (3)? b = 100.88 (3), C17H26N2O9S, Mr = 434.46, V = 1099.3 = 1.312 g / cm3, F (000) = 460, m = 0.196 mm-1, R = 0.0704 and wR = 0.1655. The total independent reflections were 5098, of which 1875 were observed with I ≥ 2s (I). The hexopyranosyl The acetoxylmethyl group is in the gauche-gauche conformation. The S atom is in synperiplanar conformation, while the NCNC linkage is antiperiplanar. X-ray analysis shows that the absolute The 1H NMR spectra and IR are in good agreement with the result of crystallography analysis. The NH ... O intermolecular hydrogen bonds link the molecules int infinite chain connected by CH ... O interactions.