Hydroxy-phenyl)-5-(2-methyl-phenyl)-6-ethoxycarbonyl-cyclohexen-2-one has been synthesized and characterized by elemental analysis, IR, UV, H NMR and MS, and its crystal 1 structure was determined by X-ray single-crystal diffraction method. The crystal belongs to the monoclinic system, space group P21/c with a = 14.6298(13), b = 5.8623(5), c = 22.255(2) ?, β = 105.855(2)o, V = 1836.0(3) ?3, Mr = 350.40, Z = 4, Dc = 1.268 g/cm3, F(000) = 744, μ(MoKα) = 0.086 mm-1, R = 0.0680 and wR = 0.1498. The crystal analysis results show that the cyclohexene unit of the title compound has a quasi-chair conformation, and a centrosymmetric dimer with a 16-membered ring is produced by the intermolecular hydrogen bonds. Hydroxy-phenyl) -5- (2-methyl-phenyl) -6-ethoxycarbonyl-cyclohexen-2-one has been synthesized and characterized by elemental analysis, IR, UV, NMR and MS, and its crystal 1 structure was determined by The crystal belongs to the monoclinic system, space group P21 / c with a = 14.6298 (13), b = 5.8623 (5), c = 22.255 ), V = 1836.0 (3)? 3, Mr = 350.40, Z = 4, Dc = 1.268 g / cm3, F (000) = 744, μ (MoKα) = 0.086 mm-1, R = 0.0680 and wR = 0.1498. The crystal analysis results show that the cyclohexene unit of the title compound has a quasi-chair conformation, and a centrosymmetric dimer with a 16-membered ring is produced by the intermolecular hydrogen bonds.