Belonging to the catalysis field, the invention provides a preparation method of an iron-based pyrrolidone ionic liquid catalyst and a method for catalysis of olefin hydrosilylation reaction with thecatalyst in order to solve the problems of high catalyst cost and non-recyclability of catalyst in current hydrosilylation reaction. The catalyst prepared by the method provided by the invention can be used for catalyzing hydrosilylation reaction of olefin and hydrogen-containing alkoxy silane, the reaction conditions are mild, the raw material conversion rate is high, and the catalyst is convenient for recycling.