This paper puts forward a novel fault location algorithm on asynchronous two-terminal data without limitation of fault types. On the basis of the equivalency of the sequence component of harmonic voltages estimated from two terminals on fault points, this paper offers a 6N-dimension-equation for fault location on asynchronous data and also applies a nonlinear states estimation method to calculate the minimum mean square optimal root. The simulation shows good stability and high accuracy of the algorithm.Th...