ABSTRACT Six new promising lines of melon (Cucumis melo L.)Were evaluated under six environmental conditions (three sowing dates in two seasons of 2019 and 2020). A randomized complete block design (RCBD) with three replicates was used for each sowing date at Kaha Vegetable Research Farm, Qalubia Governorate, Horticulture Research Institute (HRI), Agricultural Research Center (ARC), Egypt. Data were recorded for some traits i.e., average fruit weight, fruit length, fruit diameter, flesh thickness, fruit cavity, total soluble solids (TSS) and  total yield. The significant mean squares due to environment (years × sowing dates) suggested that environment (years) considerably influenced on the genotypic performance. The interactions between genotypes and environments for traits were significant indicating that genotypes behaved differently under different years, significant mean square due to environments (linear) for traits indicating the differences between years (environment) and their considerable influence on these traits. Results showed that for fruit weight L-5 had a regression coefficient (bi) near one and deviation from regression 1 (S²_d) not differant from zero. For flesh thickness results showed that L-1, L-3, L-5 had (bi) near solidarity and deviation from relapse, close to 1 (S²d) not significantly different  from zero. For total soluble solids (TSS) results showed that L-1, L-4 had (bi) close to 1 and (S²d) not significantly different  from zero. Concerning total yield results showed that L-1 and L-5 had significantly different  (bi) near unity and deviation from the regression line, close (S²d) not significantly different  from zero.