Abstract: Organic two-dimensional (2D) materials have become one of the emerging topics, due to their potential unique physical and chemical properties. The preparation of 2D polymers with large area, controllable thickness and long-range ordering features remains challenge. Many new organic 2D materials have been reported in the past few years. However, many organic 2D materials possess obvious disadvantages, including poor crystallinity, limited ordering size. Recently, Xinliang Feng's group at Dresden University of Technology reported the controllable preparation to crystalline two-dimensional polymer by surfactant-monolayer-assisted interfacial synthesis (SMAIS). The key of this method is the surfactant monolayers at the gas-liquid interface can limit molecules or precursors to the 2D interface, for further polymerization. The regulation of the repeating structure and crystallinity of as-prepared 2D polyaniline (2DPANI), 2D polyimide (2DPI) and 2D polyamide (2DPA) were very well studied. This method provides a new strategy for preparation of crystalline organic 2D polymers.