This study aimed to evaluate yield performance of cotton genotypes in different environments to know the best genotypes for produce the new variety. Thirty-eight new cotton lines descending from fifteen Egyptian cotton crosses were included in Trail A, and eighteen lines descending from thirteen crosses were included in Trail B in 2014 season using two commercial varieties Giza 80 and Giza 90 as checks. Trail A was raised at Seds, whereas Trail B was held at five locations (Seds, El-Fayoum,

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... enia, Assuit and Sohag) in Middle and Upper Egypt. The results of Trail A showed that the most of genotypes belonging to crosses exceeded significantly the check variety Giza 80 in both yield and its contributing variables. While, Trial B showed the superior of the nine crosses i.e. Deltbain 703)) significantly exceeded Giza 90 in boll weight across five locations. High heritability estimates in broad sense were recorded for most studied traits in Trail A and Trial B indicating that phenotypic selection for these strains could be highly effective. High gcv estimates were observed in seed cotton yield (9.66 and 30.08%), lint yield (10.93 and 33.17%) and number of bolls (3.16 and 2.21%) in Trial A and Trial B, respectively. The significant genotypes x locations interaction indicated that, such materials were affected by the environment and it should further be evaluated for several years at different locations.