The title compound (13,27-dimethyl-3,6,9,17,20,23-hexaazatricyclo-[23.3.1.111,15]- triaconta-1(29),2,9,11,13,15(30),16,23,25,27-decaene-29,30-diol-N3,N6,N9,O29,O30)-bis(nitrato-O,O′)- holmium(III) nitrate hydrate has been prepared and characterized by elemental analysis, infrared spectra, and electrospray mass spectra. Its crystal and molecular structures were determined by X-ray diffraction methods. The crystal crystallizes in the monoclinic system, space group C2/c with a = 23.737(12), b = 14.237(7), c = 19.801(10) , β = 91.36(1)o, Mr = 831.57, V = 6690(6) 3, Z = 8, Dc = 1.651 g/cm3, F(000) = 3344, R = 0.0482 and wR = 0.0923. The holmium ion is located in one of the compartments of the macrocyclic ligand and presents a distorted tricapped trigonal prismatic coordination geometry. The macrocycle is coordinated with two oxygen and three nitrogen atoms. Two nitrates are chelated in the opposite positions of the macrocycle, and the third one is ionic. The title compound (13,27-dimethyl-3,6,9,17,20,23-hexaazatricyclo- [23.3.1.111,15] - triaconta-1 (29), 2,9,11,13,15 (30 ), 16,23,25,27-decaene-29,30-diol-N3, N6, N9, O29, O30) -bis (nitrato-O, O ’) - holmium (III) nitrate hydrate has been prepared Its crystal and molecular structure were determined by X-ray diffraction methods. The crystal crystallizes in the monoclinic system, space group C2 / c with a = 23.737 (12), b = 14.237 (7), c = 19.801 10, β = 91.36 (1) o, Mr = 831.57, V = 6690 63, Z = 8, Dc = 1.651 g / cm3, F , R = 0.0482 and wR = 0.0923. The holmium ion is located in one of the compartments of the macrocyclic ligand and presents a distorted tricapped trigonal prismatic coordination geometry. The macrocycle is coordinated with two oxygen and three nitrogen atoms. Two nitrates are chelated in the opposite positions of the macrocycle, and the third one is ionic.