The invention discloses a method for doubly-biomimetic preparation of a super-hydrophobic membrane for membrane distillation, belongs to the field of biomimetic interface materials, and aims to solve the problems of complexity, serious environmental pollution, high cost and relatively low hydrophobicity of a super-hydrophobic membrane preparation process in the prior art. The preparation method comprises the following steps: 1, performing polymerization reaction on a matrix material in a tris(hydroxymethyl)aminomethane hydrochloride buffer aqueous solution of dopamine/polyethyleneimine to obtain a matrix material with biomimetic biogum on the surface; 2, performing drying treatment; 3, impregnating the matrix material in an inorganic nanoparticle solution with negative charges to obtain a matrix material with a rough surface structure; 4, performing hydrophobic surface modification; 5, finally performing drying treatment to obtain the super-hydrophobic membrane for membrane distillation. According to the method, damage to the chemical property of the surface of the material is prevented; a simple solution impregnation manner is adopted, so that production scaling-up is easy to implement, a process is simple, and the obtained super-hydrophobic membrane is high in hydrophobicity.