A controller controls a radiative air-conditioning equipment which cools or heats space separated from indoor, space by a radiation panel, with an air conditioner, so as to cool or heat the indoor space by a radiation effect of the radiation panel. A data collection unit collects indoor environment data and panel temperature data from an indoor environment measurement sensor and a radiation panel measurement sensor, respectively. A heat quantity determination unit acquires panel characteristics data and device characteristics data, and determines a time-series pattern of a heat quantity to be processed by the radiative air-conditioning equipment based on the acquired data and the data collected by the data collection unit. An operation instruction unit gives to the air conditioner an instruction for operating the air conditioner according to the time-series pattern determined by the heat quantity determination unit