The invention belongs to the field of coating and particularly discloses a one-component anti-pollution flashover coating for inhibiting chlorococcum growth and a preparation method thereof. The coating comprises the following components in parts by weight: 50-70 parts of dihydroxyl polydimethylsiloxane, 5-15 parts of simethicone, 5-10 parts of reinforcing agent, 10-20 parts of fire retardant, 3-5 parts of pigment and filler, 3-5 parts of cross-linking agent, 0.5-2 parts of tackifier, 0.1-1 part of catalyst and 50-80 parts of solvent. The preparation method comprises the steps of selecting and weighing raw materials, drying and preparing the sizing materials. The specific pigment and filler for inhibiting the chlorococcum growth is added in an organic silicon coating; the pigment and filler can partially absorb the light wave part for the chlorococcum growth and can reflect the light wave not good for the chlorococcum growth; a light wave environment not good for the chlorococcum growth is formed on the surface of the coating so that the chlorococcum growth can be retarded or inhibited; the construction is simple without pollution to the surrounding.