Abstract: Control device, method, machine-readable storage medium, and computer program product for a reactor are provided. The automatic control method for the reactor includes the steps of obtaining the multi-level relevant parameters of the reactor; controlling the values of the parameters of each level according to the transfer functions between the multi-level relevant parameters from level to level, so that the specified parameters are within the preset range. The automatic control method for the reactor can achieve the dynamic process adjustment and optimization of the multi-level variables of the reactor and, at the same time, maintain the stable operation of the reactor.