The invention relates to a construction method for a combined aluminum alloy template applied to an assembly type precast concrete structure. The method comprises the following steps of precasting an aluminum alloy template component, manufacturing a precast concrete component, measuring and despooling, hoisting and installing, pouring overall, and disassembling a mold; when precasting the precast concrete component, ensuring the cross-pulling threaded rod hole site of the precast concrete component and the cross-pulling threaded rod hole site of the aluminum alloy template are identical; during installation, using cross-pulling threaded rods to penetrate directly, utilizing strict command reinforcement to ensure an existing poured wall body is closely connected with a precast wall body; after completing installation of all precast concrete components and the aluminum alloy template, starting concrete pouring, and realizing one-time pouring and molding of a wall column, a beam and a plate by using the aluminum alloy template. By the construction method, the problems that in the construction of a precast concrete structure, the template at an on-site pouring position is difficult to assemble and disassemble, grout runs away or is leaked, safe and civilized construction is poor, the construction efficiency is influenced due to excessive weight and the construction quality is influenced due to deformation and decomposition are solved; the repeated use rate is high; the universality is strong; and the quality and effect are relatively good.