The invention discloses a preparation method for an electronic substrate welding assistant and belongs to the technical field of welding assistants. Aiming at the defects that a large number of halide ions are contained in residues of current electronic substrate welding flux, the electric insulation performance is lowered, and pollution is liable to occur, the preparation method adopts succinic acid and oxalic acid triethanolamine are adopted as core materials, acrylic resin serves as a shell material, and microencapsulation compound active substances are obtained; then rosin of masson pine rosin serves as raw materials to prepare maleopimaric acid polyethylene glycol ester; and finally, the maleopimaric acid polyethylene glycol ester is mixed with the microencapsulation compound active substances, benzotriazole and the like to prepare the electronic substrate welding assistant. According to the preparation method, the microencapsulation compound active substances are prepared, thus the surface activity of the welding assistant is increased, the compatibility between the welding assistant and a welding assistant is enhanced, maleic anhydride and other volatile assistants overcome the defects that the electric insulation performance is lowered due to the fact that too many halide ions are left in residues of traditional welding flux, so that the environment pollution degree is lowered, and wide economic prospects are achieved.