Compounds Ind 2Zr(OC 6H 4 p Me) 2, Ind 2Zr(OC 6H 5) 2, Ind 2ZrCl 2 and Cp 2Zr(OC 6H 4 p Me) 2 have been synthesized and formed respective catalysts A、B、C、D with Et 2AlCl. The effects of polymerization temperature, time and catalyst aging temperature on the catalytic activities and selectivities of the catalysts in ethylene oligomerization have been investigated. The order of the catalytic activity of the catalysts was A>B>C>D. Under optimal reaction conditions the activity of catalyst A was 1666 g/g·h (oligomer mass obtained by one gram Zr in catalyst per an hour) with selectivity of 92 7% for C = 4～C = 10 olefins and 86 0% for C = 4～C = 10 linear α olefins.
