Abstract: A study of the response of potato tuber yield and its component to GenotypexEnvironment (GxE) interaction was undertaken. Five cultivars of potato (Solanum tuberosum) including three new cultivars to Egypt (lady Belfour, Saxon and Bambino) were planted in order to test their stability. The evaluations were done under eight environments which consisted of 2 locationsx2 yearsx2 seasons treatment combinations. The locations were Abbies farm (Alexandria governorate- coarse clay soil) and Sadat Farm (Minufiya governorate-sandy soil). The experiment was conducted in two seasons (summer and winter seasons) of years 2007 and 2008. Combined analysis for obtained data was applied to reveal adaptability parameters and correlation coefficient among the investigated environments. All studied morphological and yield characteristics exhibited highly significant genotypic differences. The second order interaction (varietyxlocationxseason) reflected highly significant effect on all studied characters. It was obvious that the studied cultivars responded differently across environments, therefore, their ranks within environments indicated there specific adaptation which reflect the high magnitude of genotypexenvironment interaction. Data indicated that both linear (predictable) and non-linear (unpredictable) components significantly contributed to genotypexenvironment interaction observed for all studied characters. The study has identified high yielding and stable potato cultivars like Valour and lady Belfour.