A series of half-titanocene chloride 2-(benzimidazol-2-yl)quinolin-8-olates C1 C6 were synthesized by treating the lithium salts of the ligand with CpTiCl3 . All the complexes were characterized by 1H-NMR, 13C-NMR and elemental analyses, and the crystal structure of C3 and C6 was measured by X-ray. These half-titanocene complexes showed moderate catalytic activities toward ethylene polymerization (up to 1840 kg·mol-1(Ti)·h-1) when activated with MMAO, affording the high molecular weight polymers. And they also exhibited good activity for copolymerization of ethylene and α-olefin with low content of co-monomer. A series of half-titanocene 2- (benzimidazol-2-yl) quinolin-8-olates C1 C6 were synthesized by treating the lithium salts of the ligand with CpTiCl3. All based on 1H-NMR, 13C-NMR and These half-titanocene-based compounds were moderate catalytic activities towards ethylene polymerization (up to 1840 kg · mol -1 (Ti) · h -1) when activated with MMAO, affording the high molecular weight polymers. And they also exhibiting good activity for copolymerization of ethylene and α-olefin with low content of co-monomer.