The black thermal control coatings were prepared by etching anodic oxide film and coloring with an organic ATT dyestuff on the LY12 aluminum alloy. The anodic oxide film on aluminum alloy was formulated in 20% aqueous solution of sulfuric acid in galvanostatic conditions. The microstructure of the anodized coating was studied by scanning electronic microscope (SEM). Open circuit potential (OCP) was applied to study the etching of porous oxide layers in the immerging acid solution. The influence of coloring on the optical properties of the coating was investigated. Results showed that the solar absorptance and infrared emittance increased by increasing coloring times.