Preparation of polymer-clay nanobrick wall film is considered as an ingenious, effective and environment friendly strategy to prevent metal corrosion. The key point is to design and synthesize ultrathin and well dispersed clay nanosheets, which can achieve an orderly orientation in polymer matrix. Herein, we proposed a "bottom-up" strategy to direct synthesis of layered double hydroxides monolayer nanosheets (LDH-NS), and the as-prepared nanosheets was used in a brick wall hybrid film with polyvinyl butyral (PVB) via a straightforward and time-efficient assembly process. The uniform and ultrathin LDH-NS was well aligned along the substrate surface under flow induction and thus forming a highly ordered layered composite film. The present film as a barrier coating for mild steel exhibits excellent corrosion resistance in chloride solutions, because the brick wall structure could effectively inhibit the diffusion of aggressive species. This work provides a new paradigm for designing polymer-clay nanobrick wall hybrid films towards metal anticorrosion applications.