The invention discloses a preparation method for a high-selectivity dopamine platinum carbon catalyst; the dopamine platinum carbon catalyst is prepared with a dopamine precursor solution and an activated carbon-doped platinum precursor solution as raw materials. The preparation method not only solves the problems that a traditional precipitation method and a traditional impregnation method are low in activity, poor in selectivity, short in service life and the like, and also keeps the particle size distribution and particle size similar to those of a colloidal platinum catalyst.