The invention relates to an instant-type acid solution thickening agent, a preparation method therefor and applications thereof. The thickening agent comprises the following raw materials, organic alcohols, polymers and dispersing agents. The invention also relates to a preparation method for the thickening agent and applications. The prepared thickening agent has acid resistance and temperature resistance. The viscosity of a thickened acid solution deployed by the instant-type acid solution thickening agent and hydrochloric acid can be above 50mPa.s, and the viscosity loss rate is less than 10% at the temperature of 90 DEG C. The thickening agent is suitable for acidification transformation of gas wells with low pressure, low permeability and low yield.