Based on nonsinusoidal power decomposition, a method to determine the harmonic responsibility was proposed for power consumers of point of common coupling. The mechanism of harmonic transmission was analyzed for power multi-consumer. In time domain, the feeder currents were orthogonal decomposed using the distortion voltage as reference according to Fryze power theory. Inharmonic voltage, inharmonic current and harmonic current were defined; then, the consumer linearity were calculated for multi-consumer harmonic source localization. The network equations of harmonic sources were set by using multiport network theory. Because of independence and randomness the paper adopted the Independent Component Analysis to decouple feeder harmonic currents. By isolating observation vector and suing the negative entropy as objective function, the original harmonic currents were determined without considering network harmonic parameters and harmonic source characteristics. At last, the harmonic contribution was determined. Simulation results of the universality models show that the proposed method has more effective for harmonic responsibility determination. It can localize harmonic source and calculate total harmonic current.