Abstract: This paper studies the atomic oxygen (AO) erosion effects, VUV/AO ordinal effects and AO/VUV synergistic effects on the thermal control coating S781 by using AOBISEE facility. Samples were exposed to a fluence of 3.5×10¹⁹ atom/cm² AO and 200 ESH VUV. The mass of the samples was measured by high precision micro-electron balance after the test. Emissivity was measured by TEMP 2000A. For the thermal control paint S781, the synergistic effects can be shown by its mass loss, which is increased obviously after the synthetic experiment of AO/VUV. However, the emissivity is not affected significantly after the three different experiments. Results also indicate that VUV/AO ordinal experiment can not replace the AO/VUV synthetic experiment for thermal control paint S781 within the irradiation dose.