The invention relates to a measurement method for separation of convection heat and radiant heat for a wall surface. The measurement method is performed in a rectangular room with constant-temperature regulation and control, uniform air flow of supply air and return air by an indoor air conditioner and adjustable air sending volume and air sending temperature of the air conditioner, wherein one wall is taken as the measured wall surface, the surface temperature is higher than the temperature of other wall surfaces, the heat transfer quantity of the measured wall surface and the net heat radiation quantity of the measured wall surface and other wall surfaces are respectively measured by utilizing a heat flux density meter and a net radiometer, the convection heat of the measured wall surface is obtained by using the heat transfer quantity measured by the heat flux density meter to subtract the net heat radiation quantity measured by the net radiometer according to the heat balance principle of the wall surface, and the convection heat and the radiant heat of the measured wall surface are further separated. According to the measurement method provided by the invention, the load of a wall body is directly obtained by measuring the heat transfer quantity and the net radiation quantity of the wall body, the method is simple and convenient, the physical significance is clear, and errors between theory and reality caused by the load of the wall body when a reaction coefficient of theoretical calculation is adopted for calculation can be avoided.