The invention relates to a distinguishing and decision-making method and system for noninvasive power load decomposition, and belongs to the technical field of power load decomposition. The method comprises the following steps: firstly collecting electricity information of a load side by a noninvasive equipment, and extracting power load characteristics from the electricity information; decomposing the extracted power load characteristics by at least two load decomposition algorithms, and carrying out equipment distinguishing on each algorithm; and carrying out decision-making on the distinguishing result of power load decomposition by a distinguishing estimation algorithm. Household electrical equipment is simultaneously distinguished by different methods; decision-making is carried out on three distinguishing results through distinguishing and decision-making algorithms; the distinguishing accuracy is improved; and the effect of the decision-making algorithm is tested through an actual sample.