Ni(II) complexes with Schiff-bases obtained by the condensation of lysine with salicylaldehyde; 2,3-; 2,4- and 2,5-dihydroxybenzaldehyde and o-hydroxynaphthaldehyde have been synthesized using template method in ethanol or ammonia media. They are characterized by elemental analysis, conductivity measurements, magnetic moment, UV, IR, and 1H NMR spectra as well as thermal analysis (TG, DTG, DTA). The Schiff-bases are dibasic tridentate donors and the complexes have square planar and octahedral structures. The complexes thermally decompose in two or three steps where kinetic and thermodynamic parameters of the decomposition steps are computed. The interactions of the formed complexes with FM-DNA were monitored using UV and florescence spectroscopy.