The invention provides an opening adjusting device of an expansion valve. The opening adjusting device comprises a fixing unit and an adjusting unit. The fixing unit is used for fixing the expansion valve, and the expansion valve comprises an opening adjusting portion used for adjusting the opening degree; the adjusting unit comprises an adjusting head; and under the state that the expansion valve is fixed to the fixing unit, the adjusting head is matched with the opening adjusting portion in a driving manner. Through the application of the technical scheme, after the expansion valve is fixed, the opening of the expansion valve is adjusted, and the adjusting efficiency is effectively improved.