Abstract: A preparation method (100) for a three-dimensional micro-nano morphological structure manufactured by a laser direct writing lithography machine, comprising: step 110, providing a three-dimensional model diagram; step 120, dividing the three-dimensional model diagram in a height direction to obtain at least one height interval; and step 130, projecting the three-dimensional model diagram onto a plane to obtain a mapping relationship, wherein the mapping relationship comprises coordinates, on the plane, corresponding to each point on the three-dimensional model diagram, and wherein the height of each point on the three-dimensional model diagram corresponds to a height value in a corresponding height interval; and making the mapping relationship correspond to an exposure dose according to the mapping relationship, and performing lithography on the basis of the exposure dose. Any three-dimensional micro-nano morphological structure can be obtained.