The invention relates to an etching solution for a copper-molybdenum alloy film. The pH value of the etching solution is 1-2. The etching solution comprises, by mass, 1%-5% of hydrogen peroxide, 0.1%-10% of inorganic acid, 0.5%-10% of sulfate, 0.5%-15% of inorganic ammonia salt buffering agents, 0.01%-10% of alcohol amine pH modifiers, 0.1%-10% of hydrogen peroxide stabilizers, 0.1%-5% of metal ion chelating agents, 0.01%-5% of metal inhibiters, and the balance deionized water. According to the etching solution for the copper-molybdenum alloy film, a small quantity of hydrogen peroxide is added and assisted with the metal inhibiters and inorganic acid, and the substances such as the sulfate and the inorganic ammonia salt buffering agents are added, so that the change of the pH value of an etching solution system is kept within +0.3 all the time in the etching process; the stability of the pH value of the etching solution system in the etching process can be kept, and nonuniform etching caused by an excessively-low pH value can be avoided; and in the process that the content of copper ions changes from 0 ppm to 1000 ppm, the etching speed is not changed, the etching CD and the slope angle are basically unchanged, etching residues are avoided, and the requirement of customers for high-precision machining is met.