A controlling device for indoor apparatus includes a detection module, a human machine interface (HMI) and a wireless transmission module. The controlling device accepts supervisor's setting for an indoor electronic apparatus via the HMI, detects the environment around the controlling device for generating a plurality of detection value via the detective module, and receives another detection value from a plurality of slave detection devices in same controlling system. The controlling device generates a control command based on setting parameter of the supervisor and the plurality of detection value, and transmits the generated control command to the indoor electronic apparatus via the wireless transmission module. The indoor electronic apparatus works based on the received control command, so the environment around the controlling system can satisfy supervisor's demand.