The invention belongs to the field of casting construction of concrete embedded parts, and particularly discloses a method for arranging expansion joints in a concrete embedded part. The method comprises the following steps: casting concrete, arranging an embedded part on the surface of the concrete and carrying out surface finishing on the concrete. In the process of carrying out surface finishing on the concrete, a plate type tool, close to the side of an exposed surface of the embedded part, is vertically inserted into the concrete, and the plate type tool is taken out after the concrete is initially set; and depth of inserting the plate type tool into the concrete is equal to the thickness of the embedded part. Under the control of the plate type tool, the method guarantees that the expansion joints in the embedded part are consistent in width and depth while damages to the embedded part are avoided; the expansion joints are reserved during the surface finishing of the concrete, so that the construction time is saved, the construction cost is reduced, the construction is convenient, the operation is simple, the construction quality is guaranteed, and popularization and application are easy.