A method and a system for estimating use time of electric appliances are provided. In the present method, all time points corresponding to an appliance power on event or an appliance power off event are obtained according to a value-time curve of at least one electric characteristic. A characteristic value of each of the time points is calculated according to the value-time curve, so as to pair the time points corresponding to the appliance power off event with the time points corresponding to the appliance power on event appropriately. After the pairing process is accomplished, the use time of each of the electric appliances can be calculated by the paired time points and thereby the power consumption of the electric appliances can be figured out.
