The invention provides a reversed phase emulsion splitter, which is a product of the combination of long-chain alkyl 1.0G polyamide-imide and long-chain alkyl benzenesulfonic acid in a solvent, wherein the long-chain alkyl 1.0G polyamide-imide is a compound of a general structural formula I and the long-chain alkyl benzenesulfonic acid is a compound of a general structural formula II; in the formula I, R1 is an alkyl of which the main chain has 6 to 28 carbon atoms; and in the formula II, R2 is an alkyl of which the main chain has 6 to 24 carbon atoms. The reversed phase emulsion splitter has high emulsion splitting performance for O/W type emulsions and can be used in the field of the low-temperature dehydration of reversed phase emulsions and the treatment of oil-containing waste water.