As a kind of white paint, ZnO/silicone thermal control coatings are used commonly in space. In order to implement more effective thermal control in space, nanotitanium dioxide was doped to the coatings. In this paper, different percent of nanotitanium dioxide was appended to the coatings, and thermal control principle was discussed. Optical properties of these coatings were discussed by spectrophotometry and infrared reflectometer. The experimental results show that solar absorptance (αs) of nanotitanium dioxide doped ZnO/silicone thermal control coating is lower in all wavelength region than the coatings without doping, especially in visible region and infrared region. The total solar absorptance of 1% nanotitanium dioxide doped coating is 0.09, which decreases by 36% than the undoped coating..