Developed GIS automated multicriteria analysis (GAMA) method presented in this article allows automation and simplification of multicriteria GIS decision analysis (GIS-MCDA) susceptibility modelling. Traditional GIS-MCDA susceptibility modelling still represents time and labor demanding process, whose success is highly influenced by the user's experience and knowledge. In order to make overall GIS-MCDA susceptibility modelling process more straightforward and practical, GAMA method is designed as easy to use three step process, which allows automation of following GIS-MCDA steps: (1) , (2) and (3) . GAMA method is developed within ArcGIS 10.4 ModelBuilder application, as a toolset that can be easily shared and incorporated within default ESRI's ArcGIS toolbox. GAMA was successfully applied for gully erosion susceptibility modelling on example of Pag island, Croatia, whose results are published in separate article. Since GAMA method is applicable to various GIS-MCDA susceptibility modelling purposes we are encouraging its future use and therefore open-source GAMA method toolset can be acquired for research purposes (htps://gal.unizd.hr). •GAMA method simplifies overall GIS-MCDA susceptibility modelling process.•GAMA allows automated standardization, grouping, weight coefficient assignment and aggregation of GIS-MCDA's criteria.•GAMA method has broad application in various different GIS-MCDA susceptibility modelling purposes.