Abstract: This paper reviews the advances in non-metallocene ⅣB group metal catalysts for olefin polymerization according to the type of ligands, including amidos, ketimides, pyrazoles, and phenoxyimine. The effects of steric structure and electronic effect of ligands on catalytic activity, polymer structure and molecular weight of the polymer are discussed. The merits of highly active non-metallocene ⅣB group metal catalysts for olefin polymerization are summarized.