A method for identifying an electric appliance and an apparatus and a system thereof are provided. The method includes the following steps: respectively collecting a first power event on a first phase power and a second power event on a second phase power; when the first power event and/or the second power event are collected, determining whether the first power event and the second power event substantially occur at the same time; if not, identifying an unknown electric appliance as a first type electric appliance; and if yes, determining whether the first power event and the second power event are substantially the same, wherein if yes, identifying the unknown electric appliance as a second type electric appliance, and if no, identifying the unknown electric appliance as the first type electric appliance.