The present invention belongs to the technical field of aircraft icing ice-shaped measurement, and especially relates to a developing agent for aircraft icing ice-shaped three-dimensional scanning anda preparation method thereof. The developing agent comprises TiO2 powder, PMMA powder and a dichloromethane solvent. The preparation method comprises the steps of: pouring the TiO2 powder and the PMMA powder into a beaker, pouring dichloromethane into the beaker along a beaker wall by employing a measuring cylinder, and performing pre-stirring with pouring to obtain pre-mixed solution; and employing a ball-milling blender to perform stirring of the pre-mixed solution to make the developing agent. The problem is solved that the ice-shaped light transmittance is too high and cannot meet the laser three-dimensional scanning requirement, the provided developing agent has good adhesive force for the ice shape so that the ice-shaped light transmittance is greatly reduced, light shielding effectduration is long, secondary icing or ice melting cannot be caused, the developing agent for aircraft icing ice-shaped three-dimensional scanning is environmentally friendly and low-toxic, easy to spray, and has a very important practical significance for promotion of the application of the laser three-dimensional scanning technology at the aircraft icing ice-shaped three-dimensional measurement technology.