This invention generally relates to a method for modulating interfacial wettability of a noncovalent nanoscopic monolayer or thin film. Particularly, this invention relates to a method for modulating interfacial wettability of a two-dimensional (2D) material using a molecular layer prepared from a polymerizable amphiphilic monomer having a hydrophilic head and a hydrophobic tail, wherein enhanced or decreased wettability of said 2D material is achieved by proper allocating the position of polymerizable group relative to the hydrophilic head and the hydrophobic tail.