Disclosed is a catalyst component for olefin polymerization. The catalyst component comprises magnesium, titanium, halogen and an internal electron donor. The internal electron donor includes an imine compound with a ketone group as shown in Formula I. Disclosed further is a method of preparing the catalyst component, and a catalyst for olefin polymerization containing the catalyst component. When the catalyst is used in olefin polymerization reaction especially propene polymerization reaction, the catalyst has a high long-term activity and good hydrogen response, and the obtained polymer has characteristics of an adjustable isotactic index and a relatively wide molecular weight distribution.