A series of gold(III) complexes were prepared from the reactions of HAuCl4·3H2O with 1,10-phenanthroline and its derivatives (1,10-phenanthroline (phen) in 1, 5-methyl-1,10-phenanthroline (5-Me-phen) in 2, 5-chloro-1,10-phenanthroline (5-Cl-phen) in 3, 5-nitro-1,10-phenanthroline (5-NO2-phen) in 4 and 5,6-dimetyhyl-1,10-phenanthroline (5,6-Dime-phen) in 5) ligands in a mixture of CH3CN/CH3OH at 45 °C. Suitable crystals of these complexes for diffraction experiment were obtained by slow evaporation of their solution at room temperature. Resulted complexes were characterized by elemental analysis, IR, UV–Vis absorption, 1H NMR spectroscopy and single crystal X-ray diffraction. The X-ray structural analysis indicated that the structures of 1 and 2 contains one [Au(5-X-phen)Cl2)]+ (X is H in 1 and is –CH3 in 2) cationic part and one [AuCl4]¯ anionic part. The structures of 3 and 4 consist of one [5-X-phen.H]+ (X is Cl in 3 and is NO2 in 4) cationic part and one [AuCl4]¯ anionic part. Also, the structure of 5 has one [Au(5,6-Dime-phen)Cl2]+ cationic part and two half of [AuCl2]¯ anionic parts. In the anionic part of complexes 1-4, the Au(III) cation is square planar geometry while in the anionic part of complex 5, the Au(I) cation is linear geometry. The compounds of 1 and 2 are mixed gold(III/III) complexes, compounds of 3 and 4 are proton transfer complexes and compound 5 is mixed valence gold(III/I) complex.