The invention relates to a pre-assembled window body. The pre-assembled window body comprises a main unit and at least one auxiliary unit, wherein the main unit comprises two vertical beams and two cross beams; the two vertical beams and the two cross beams are sequentially connected end to form a square structure; at least one middle beam is arranged between the two vertical beams; a plurality offirst connecting beams are arranged on the outer side face of at least one vertical beam in the longitudinal direction of the vertical beam; a plurality of strip-shaped holes are formed in each firstconnecting beam at equal intervals in the transverse direction of the first connecting beam; each auxiliary unit comprises a side beam; a second connecting beam corresponding to the corresponding first connecting beam is arranged on the side face, facing the main unit, of each side beam in the longitudinal direction of the side beam; and a plurality of through holes corresponding to the strip-shaped holes are formed in each second connecting beam at equal intervals in the transverse direction of the second connecting beam. The pre-assembled window body has the advantages that the constructionprocedures of a construction site are reduced, the construction period is effectively shortened, and the assembled window body is good in linearity.