Abstract: In order to solve the broken roadway support failure problem under the acidic water corrosion condition, the formation process of acidic water is analyzed and the acidic water component is detected in typical area to analyze the damage mechanism of acid water to roadway support.By consulting the relevant literature, it is proposed to add an appropriate amount of fly ash to the concrete to improve the corrosion resistance of the concrete.The strength test of the concrete specimens with different fly ash additions under the acidic corrosion conditions of dry and wet cycles is carried out, and finally the concrete corrosion resistance is best when the amount of fly ash added is 20%.Based on the analysis of the stress distribution of the roadway, the optimization scheme of roadway support under acidic water corrosion conditions is proposed.The total cost of the new scheme is reduced by 348 yuan/m compared with the old scheme and the reduction ratio is 27.8%.