Tetra coordinated copper(II) complex of formula [Cu(L1)(imid)] is synthesized using imidazole and a tridentate O,N,O hydrazone ligand L1 prepared by condensation of 1,1,1-trifluoropentanedione and 4-chlorobenzhydrazide. The ligand and complex are characterized by UV-Visible, FTIR, NMR, mass and single crystal XRD techniques. DNA binding mode is assessed by UV absorption, fluorescence spectral and circular dichroism studies. Based on the results, it is observed that complex has preferred intercalative mode of binding with DNA. The binding constant, Kb, was found to be 4.02 ± 0.09 × 104 M- 1. Thermodynamic parameters such as ΔH, ΔS and ΔG obtained from acridine orange fluorescence displacement assay revealed that the hydrophobic and hydrogen bonding interactions are playing a major role in the binding pattern. In addition, cytotoxicity of the complex towards MCF-7 breast cancer cell line has also been assessed. © 2016 Elsevier B.V. All rights reserved.