Two field experiments were carried out at Sakha Agricultural Research   Station, Kafr El-Sheikh Governorate, Egypt, during 2016 and 2017 summer seasons to study the effect of water deficit on growth, yield and quality of seed of 12 soybean genotypes. Water deficit regimes were applied at 15 (recommended  regime), 20 and 25 days   intervals. The results of combined analysis showed significant effects of soybean genotypes, irrigation regimes and their interactions on the studied traits. Water   deficit significantly decreased 100-seed weight and seed yield/feddan in both seasons. Irrigation intervals significantly influenced seed quality traits such as oil, protein, germination percentage and electrical conductivity. The 20 days interval regime resulted in high 100-seed weight and seed yield, while the 25 days interval regime gave lower values in this respect. The percentage of oil and protein of seeds was significantly affected by water deficit, where there was a decrease in seed oil and an increase in protein content. Water deficit significantly decreased dry matter accumulation, leaf area index, crop growth rate, net assimilation rate and chlorophyll content in leaves, while relative water content and proline were significantly increased. The commercial cultivar Giza 111 produced high 100 seed weight (19.84 g) and seed yield (2.183 t/fed), followed by H14L8. On the other hand, seed germination (%) was decreased with increasing water deficit, while seed conductivity (vigor test) was increased. Giza111 showed  high seed germination percentage over all irrigation regimes with (87.1%) as an average, whereas Toano gave low seed germination percentage (73.2%). Generally, the genotype Giza111 is the most suitable genotype under the different irrigation regimes, whereas 416937 and DR 101 genotypes could be useful for soybean breeding program for water deficit tolerance.