Bis(p-hydroxybenzaldehyde) Schiff base containing piperazine ring，N,N'-bis(4- hydroxybenzyl)-1,4-bis(3-iminopropyl)piperazine, was synthesized with 1,4-bis(3-amino- propyl)piperazine (BAPP) and p-hydroxybenzaldehyde (PHBA) as raw materials. The structure of the product was characterized by means of elemental analysis, IR, 1HNMR and UV-vis spectra. The interaction of the title compound with CT-DNA was investigated by UV-vis absorption spectroscopy and viscosimetry. The hypochromic effect and red shift were observed in the UV-vis absorption spectra, and the relative viscosity of CT-DNA increased with the addition of the title compound. The results indicated that the bis-Schiff base binds to CT-DNA by intercalation mode.