Torrential floods are the most frequent natural hazard events in Bosnia and Herzegovina. The increase of intensive rains in Bosnia and Herzegovina over last years, as a consequence of the climate changes, has triggered many torrential floods, which have generated a lot of damages and losses of human lives. This study was focused on development of torrential susceptibility model using GMM Method and GIS in the Vrbas river basin as an attempt to create a new methodological approach which can be used on other river basins in Bosnia and Herzegovina. First, a total of 174 torrential basins were identified in the Vrbas river basin, as a base for creating an inventory map, which was a base map for the assessment of torrential floods susceptibility. The GIS Matrix Method and six influencing factors were used for generation of Torrential Flood Susceptibility Model. Based on the obtained values of Torrential Flood Susceptibility Model for the Vrbas river basin, 45.52% of the study area is within strong and very strong susceptibility category. The Torrential Flood Susceptibility Model was validated using a “degree of fit” method. Validation indicators of the TFSM show that the 80.04% are in the category of strong and very strong susceptibility, while only 4.37% are in the category of very low and low susceptibility. This fact suggests that used methodology based on GMM method and used influencing factors enable delimitation of the area with high and very high susceptibility to torrential floods into the Vrbas basin. Therefore, used methodological approach represents a good base for future research, and it has potential for the practical use and should be tested in other river basins in Bosnia and Herzegovina.