Basement double-exterior-wall post-cast strip single-side formwork supporting system

The utility model discloses a basement double exterior wall post-cast strip unilateral formwork system which comprises a formwork laid on the outer side of a post-cast strip, a plurality of parallel secondary keels are fixed to the outer side of the formwork at intervals, and the two sides of the secondary keels extend to the basement exterior wall on the outer side of the post-cast strip and are fixed through tying of embedded screws embedded in the basement exterior wall. The embedded screws are correspondingly embedded in the basement exterior walls on the two sides of the post-cast strip, water stop pieces are vertically fixed to rod bodies, located in the basement exterior walls, of the embedded screws, and the inner side ends of the embedded screws do not exceed the positions, away from main reinforcements on the sides of formworks, of the basement exterior walls; the outer side ends of the auxiliary keels sequentially penetrate through the basement outer wall and the formwork and are pressed and fixed