Catalyst component, catalyst and method for olefin polymerization

The present invention provides a catalyst component, a catalyst and a method for olefin polymerization, the catalyst component contains a titanium element, a magnesium element, a chlorine element and an internal electron donor, the magnesium element is from a magnesium-containing compound having a structure represented by formula (1), and the chlorine element is from a chlorine-containing compound having a structure represented by formula (2). The internal electron donor is selected from at least one of aliphatic carboxylic ester, carboxylic ester containing cyano, aromatic carboxylic ester with a general formula (2), alcohol ester compounds, ether compounds, ketone compounds, nitrile compounds, amine compounds, imine compounds and silane compounds. When the catalyst provided by the invention is used for olefin polymerization, the polymerization activity is good, no anisotropic material appears basically, the hydrogen regulation sensitivity is obviously higher than that in the prior art, and the catalyst has