This study was conducted during the three successive seasons, 2016/ 2017, 2017/2018 and 2018/2019 at Giza Research Station, Onion Research Department, Field Crops Research Institute, Agriculture Research Center, Ministry of Agriculture. The objective of the study was evaluating eight onion genotypes and their crosses to forming new improved composites and bi-parental onion populations. Eight onion genotypes included six exotic onion genotypes and two Egyptian onion cultivars. The eight genotypes were selected as wide diverse genotypes and representing a broad genetic base were used as parent seed to forming a new improved composites or bi-parental populations. The 8 parents and their 16 crosses were evaluated in two seasons in field experimental trial; RCBD with three replicates was used. Genotypes (parents and their crosses) were significantly differed for all studied traits (number of days to maturity, total, marketable and culls yield ton/fed, percentage of total soluble solids %, dry matter content% and total weight loss%. The lowest number of days to maturity was observed for parents P₆, P₂ and P₃, for composites in C₆ and C₃ and for bi –parental in B₃, B₂ and B₆. The highest total yield was recorded for parents by P₈ and P₇, for composites with C₄, C₇ and C₁ and for bi –parental with B₈, B₇ and B₄. The highest marketable yield was detected for parents with P₇, P₃ and P₆, for composites with C₄, C₁ and C₇ and for bi –parental with B₇ and B₄. The lowest culls yield was shown for parents with P₁, P₄ and P₃, for composites with C₃, C₆ and C₅ and for bi –parental with B₇, B₅ and B₂. Highest values of TSS% were exhibited by parents P₅, P₇ and P₈, for composites C₈, C₆ and C₇, for bi–parental B₇, B₈ and B₁. The highest values of dry matter % were observed with parents P₅, P₇ and P₈, for composites C₈, C₇ and C₅ and for bi–parental B₇, B₁ and B₈. The lowest values of total weight loss% were detected for parents, P₅ and P₁, for composites, C₅ and C₈, and for bi–parental, B₃, B₅ and B₇.