The invention belongs to the technical field of fine chemistry, and in particular relates to a method for preparing a hindered phenol antioxygen 1010. According to the method provided by the invention, beta-(3,5-ditert-butyl-4-hydroxyphenyl)methyl propionate and pentaerythrotol are used as raw materials and are subjected to ester exchange reaction to obtain the hindered phenol antioxygen 1010; the ester exchange reaction is carried out in an alkaline ion liquid catalysis system. According to the method provided by the invention, alkali ion liquid is used as a catalyst and the catalytic activity is high; the content of a product reaches 97.5 percent or more, and the yield reaches 95 percent or more. The performance of the alkaline liquid catalyst in 1010 esterification reaction is better that that of catalysts including lithium acetate, sodium methoxide, potassium tert-butoxide, organic tin and the like. An ion liquid catalytic reaction system is used and is environmentally friendly; the catalyst can be cyclically utilized; a product is not easily colored, has high yield and does not contain heavy metal.