This investigation was carried out at Sakha Agric. Res. Stat. KafrelSheikh, Agric. Res. Centre, Egypt, during 2014 and 2015 growing seasons. A study was undertaken on some genotypes of Egyptian cotton (Gossypium barbadense L.) to estimate the mean performance, heterosis over better parent (heterobeltiosis), combining ability and type of gene action for some earliness, yield and its components traits in some Egyptian cotton genotypes by using line x tester mating design between seven cotton genotypes i.e.,