The present invention relates to an isoheptane solvent oil dearomatization method based on antimony pentachloride, wherein isoheptane solvent oil and antimony pentachloride are mixed, the mixture is conveyed into a reaction kettle, a catalyst carrier is added to the reaction kettle, the aromatic hydrocarbon in the isoheptane solvent oil reacts with the antimony pentachloride to generate the chlorinated aromatic hydrocarbon having the high boiling point, the mixture obtained after the reaction is further cut and fractionated, and the distillate at a temperature of 83-95 DEG C is collected so as to obtain the dearomatized isoheptane solvent oil. With the isoheptane solvent oil dearomatization method of the present invention, the isoheptane solvent oil is effectively dearomatized, the process is simple, and the aromatic hydrocarbon removing rate is high.