The invention relates to a catalyst for olefin polymerization. The catalyst comprises a complex whose chemical structural formula is shown as Formula (I) as the main catalyst. In the Formula (I), the X stands for halogen; the values of the R1-R8 can be identical or different; the R1-R8 are respectively and independently selected from hydrogen atom, halogen, C1-C20 alkyls, heterocyclic compound group or organic groups containing oxygen atom, nitrogen atom, boron atom, sulfur atom, phosphorus atom, silicon atom, germanium atom or tin atom; and loops are optionally formed by the R1 and the R2 as well as the R5 and the R6 mutually. And the invention also provides an olefin polymerization method, wherein the olefin polymerization method comprises the step of carrying on olefin polymerization reaction under the existence of the olefin polymerization catalyst provided by the invention.