The HL ligand was synthesized in the reaction of thiosemicarbazide and 2-acetylthiazole in molar ratio 1:1 in water, with 3 drops of 2M HCl. Complex [Fe(L)2]BF4·H2O (1) was synthesized in the reaction of ligand and Fe(BF4)6·6H2O in MeOH, after complete dissolution of Fe(BF4)2·6H2O in the reaction mixture, NaN3 was added. In the reaction of ligand (HL), MnCl2·4H2O and NaN3, in the molar ratio 1 : 1 : 4, Mn(II) complex (2) was obtained. Complexes 1 and 2 were characterized by elemental analysis, IR and UV/Vis spectroscopy, and X-ray crystallographic analysis. Both complexes 1 and 2 with HL ligand are bis octahedral complexes in which two deprotonated ligand molecules coordinate in a mer arrangement through two NNS sets of donor atoms, through thiazole and imine nitrogens and thioenolate sulfur.