Abstract: A control method for surveillance system includes the steps of: detecting a region of interest by an infrared sensor; generating a trigger signal by the infrared sensor when the infrared sensor detects a moving object in the region of interest; receiving the trigger signal by a controller and determining accordingly thereby whether to generate an enable command; taking pictures of the region of interest to generate an image thereof, by an infrared camera, when the infrared camera receives the enable command; receiving the image by the controller and determining accordingly thereby whether the image meets an illumination-related criterion; sending an illumination command by the controller when the image meets the illumination-related criterion; and emitting visible light by a lamp when the lamp receives the illumination command.