Toshky as a new virgin area in the south valley is interesting for clean agriculture production free from pollution, increase Egyptian na­tional income and decrease imports. This investigation was conducted at Toshky (22' 25 N latitude and 31' 50 E longitude) during the two suc­cessive summer seasons 2001 and 2002 to study the performance of Giza 111, Giza 22, Giza 35 and Crawford soybean cultivars under five sowing dates viz. May 1, May 11, May 21, May 31 and June 10. The wa­ter requirements are 3647 m³/fed. This amount was distributed by sprinkler irrigation system during different growing stages. It included 20 % from the calculated water requirements for leaching. The soil analysis indicated that many fragments of various rock and small gravels differing in shape, size and colour dominate on the soil surface. The soil taxonomy classified as Typic xerofluvants, sandy loam, mixed and hyperthermic. The soil salinity, organic matter as well as soil fertility including macro and micronutrients are very low. The recorded data showed that Giza 22 was the best cultivar from the all studied characters. A reduction in the yield of soybean happened due to the late of planting alter May 21. The greatest seed yield (1283 kg/fed.) was obtained by Gin 22 at May 21 date of planting. From this study it can be recommended that cultivars Giza 22, Giza 35 and Giza 111 were the suitable cultivars to be planted from the first of May to May 21 under Toshky conditions. Seed yield/ plant was correlated positively with each of plant height, number of pods/plant, number of seeds/plant. 100-seed weight and harvest index.