The invention relates to the technical field of building construction, and particularly relates to a novel prefabricated insulating component and a construction method thereof. The prefabricated insulating component is composed of a prefabricated reinforced concrete plate, a prefabricated insulating board and hoopings; the prefabricated reinforced concrete plate and the prefabricated insulating board are mutually connected through an adhesive or a connector; one end of each hooping is embedded in the prefabricated reinforced concrete plate; and the other end of each hooping passes through and extends out of the prefabricated insulating board. The prefabricated insulating component is good in heat-insulating property and endurance property, low in construction cost, and simple in appearance. The prefabricated component and a cast-in-place component are relatively reliably connected by reasonable structure arrangement, so that the prefabricated component is very convenient to transport, and further the construction quality and the construction efficiency can be effectively improved; and the prefabricated structure is suitable for industrial production.