We developed a method that predicts avalanche paths deviating from a stream on complex surfaces. This method is based on Nohguchi’s center-of-mass model with simple dynamic resistance. Avalanche paths from many starting points were calculated at two sites in Japan where avalanche disasters have occurred, and paths causing unexpected disaster are presented. The characteristics of avalanche paths at these sites are shown. Small differences of the release positions sometimes cause great changes in avalanche meanderings.