Two field experiments were conducted during seasons 1999 and 2000 to study the effect of the rate and time of application of two herbicides basagran (bentazone) and starane (fluroxypyr) on the crop characters and chemical composition of sorghum grains cultivar (Shandaweel –1 hybrid) Basagran and starane were used at rate of 400, 500ml/ feddan and 100, 200ml/ feddan after 7, 15 days from sowing and hand hoeing twice after 20, 30 days form sowing. The results showed that all treatments gave a significant increase in protein and oil contents of the grains while decrease in phenols and tannins contents. Also all treatments affected slightly on carbohydrates, amino acids contents and fatty acids composition, relative percentage of unsaponifaible matter and electorphoretic protein patterns of sorghum grains comparison with the control. On the other hand, all treatments except basagran 400ml/ feddan after 15 days from sowing and hand hoeing gave a significant increase in plant height, whereas all treatments except basgran 400 and 500ml/ feddan after 15 days from sowing and hand hoeing gave a significant increase in ear length, while all treatments gave a significant increase in weight of grain / ear and 1000 grain weight whereas all herbicidal treatments except basagran 400 ml/ feddan after 15 days from sowing gave a significant increase in grain yield.