A series of N^N^N tridentate chromium complexes (C1–C6) bearing 2-(1H-2-benzimidazolyl)-6-(1-(arylimino)ethyl)pyridine derivatives was synthesized and characterized by elemental and spectroscopic analysis along with single-crystal X-ray crystallography. X-ray crystallographic analyses reveal chromium complex C1 as a distorted six-coordinated octahedral geometry. On treatment with modified methylaluminoxane (MMAO), the chromium complexes exhibited high activities for ethylene oligomerization (up to 1.50×106gmol−1(Cr)h−1) and polymerization (up to 2.06×106gmol−1(Cr)h−1) at 10atm ethylene pressure. Various reaction parameters were investigated in detail, and less steric hindrance and electron-withdrawing substituents of ligands enhance the catalytic activities of their chromium complexes.