Communication: A novel highly active catalyst 2,6-bis[1-(2-methylnaphthylimino)ethyl]pyridineiron(II) chloride (1) is reported for ethylene polymerization. Compared with 2,6-bis[(1-naphthylimino)ethyl]pyridineiron(II) chloride (2) reported recently, catalytic activities of this new complex are high with maximum activity 6.51x10(6) g PE.mol(-1).Fe.h(-1).bar(-1) at 40 degreesC. The activity of the catalyst, and the molecular weight and melting temperature of the polymers depend on the methylaluminoxane/1 molar ratio and polymerization temperature.