The invention discloses an aromatic sulfinic acid compound preparation method, comprising using chlorine aluminic acid ion liquid as a catalyst, obtaining aromatic sulfinic acid by an Friedel-Crafts acylation reaction of an aromatic compound and sulfur dioxide. Among the aromatic compounds, benzene series compounds and naphthalene series compounds are preferred. The method of the invention is mild in reaction condition and short in reaction time. The yield of benzene series products is more than 80% and the yield of naphthalene series products is more than 70% and the product content is more than 92%.