In this paper, 2-hydrazino-6-methoxy-1,3-benzothiazole was introduced into diethylenetriamine pentaacetic ( DTPA) by acylation reaction. The correspond­ing non-ion Gd(III) complex holding promise of a single molecule magnetic resonance imaging (MRI) contrast agent was obtained by treating this ligand with GdCl3·6h2 O. The efficacy of the contrast agent was assessed by measuring the longitudinal relaxivity (r1), the r1 of Gd(III)-DTPA-bisbenzothiazole hydrazide was up to 6.44 mM-1·s-1, which was 1.8 times higher than that of the analogous MRI contrast agent Gd(III)-DTPA(r1 = 3.64 mM-1·s-1) in commercial use. In addition, in vitro MR images on a 0.5 T magnetic field exhibited a remarkable enhancement of signal contrast for Gd(III)-DTPA-bisbenzothiazole hydrazide than Gd(III)-DTPA. These results demonstrate that this non-ion Gd(III) complex acts as a potentially MRI contrast agent.Scheme 1. Synthesis of ligand(H3L) and complex(Gd(III)-L)