Cast-in-place wall forming device and construction method thereof

The invention relates to the field of buildings, and particularly provides a cast-in-place wall forming device and a construction method thereof. The cast-in-place wall forming device comprises a prefabricated wall, a first formwork set, a second formwork set and a pulling sheet. The prefabricated wall is provided with a connecting surface connected to the cast-in-place wall; the first formwork set comprises two first formwork members, the two first formwork members are clamped to the prefabricated wall, and one side of each first formwork member is flush with the connecting surface; the second formwork set comprises two second formwork members, and the two second formwork members are connected to the sides, flush with the connecting surface, of the different first formwork members correspondingly; and the pulling sheet is arranged between the first formwork set and the second formwork set. The prefabricated wall is clamped by the two first formwork members and then fixed through the pulling sheet, the pullin