A method for preparing a bifunctional film, including: (a) drying a first polymer solution to form a film to form an anti-adhesion layer； and (b) drying a second polymer solution over the anti-adhesion layer to form a film to form an attachment layer. The first polymer solution includes a first hydrophobic solution and a first hydrophilic solution, and in the first polymer solution, the weight ratioi of the solute of the first hydrophobic solution to the solute of the first hydrophilic solution 1:0.01-1. Moreover, the second polymer solution is consisting of a second hydrophilic solution.一種製備雙功效薄膜的方法，包括：(a) 將一第一高分子溶液乾燥成膜，以形成一抗沾黏層；以及(b) 將一第二高分子溶液乾燥成膜於該抗沾黏層之上，以形成一貼附層。該第一高分子溶液包括一第一疏水性溶液與一第一親水性溶液，且於該第一高分子溶液中，該第一疏水性溶液之溶質與該第一親水性溶液之溶質的重量比為1:0.01-1。又，該第二高分子溶液係由一第二親水性溶液所組成。
