Abstract: Space environment test is an important way to validate the reliability of spacecraft,and its temperature dis-tribution and variation characteristics are essential for system design.The present study took a typical parabolic antenna structure as the object,analyzed its thermal balance characteristics in the thermal cycling test system,and established the heat transfer model under different radiation coefficients,external heat fluxes,and equivalent thermal conductivities.The temperature characteristics of the antenna,such as body averaged temperature,surface averaged temperature and tempera-ture standard deviation were quantitatively analyzed by numerical simulation,and the influence of different heat transfer forms on the temperature characteristics is investigated.The results show that when the external heat flow varies from 0 to 1 500 W·m^-2,the temperature of the parabolic antenna tends to be symmetrically distributed,the body average tempera-ture increases by 30 K,the standard deviation of the temperature of surfaces changes by 1.5 K,and the total pressure caused by air decreases by 2.4 N.When the equivalent thermal conductivity varies from 20 to 200 W·m^-1·K^-1,the body average temperature of the parabolic antenna increases by 2.8 K.The effect of the radiation coefficient on the standard deviation of temperature is insignificant,but it determines the direction of convective heat flux on the wall.