In this work, the ability of different sorghum cultivars to germinate under the influence of different environmental conditions was investigated. Cultivars G15 and Sh305 expressed higher percentages of seed germination and seedlings growth than those of Dorado and Sh306 cultivars under the influence of relatively high temperature and concentration of PEG or NaCl. In comparison to control, extremism in temperature, drought and salinity lead to high increase in the activity of antioxidant enzymes (SOD, CAT, APX and POX). Relative increase of SOD activity was lower but that of CAT, APX or POX was higher in Sh305 and G15 than those of Dorado and Sh306. Under the highest stress conditions, total Units g-1 FW of the studied four enzymes of Sh305 and G15 were more than those of Dorado and Sh306, it indicated that the balance between production of reactive oxygen species and scavenging enzymes were more effective in Sh305 and G15. No difference was detected between the RAPD and ISSR clusters. The obtained dendrograms were not related to the ability of the tested cultivar to germinate under studied stress conditions where one of the two close cultivars was tolerant (Sh305) but the other was sensitive (Sh306).