A B O, Rh, MNSs, Kell and Lewis blood groups and also secretor and nonsecretor system in 97 samples from hospitals and 97 samples as control group have been studied in Dasht Mishan, Khuzistan, Iran. The results showed that there exists a relatively high frequency of the B(0.278), K(0.53) and Du(0.166) genes compared to the neighbouring populations. They also showed a high frequency of cDe(0.206) and that of MN(55.67-58.76). Hospital samples and the control showed significant differences for the B, Se and se genes and also for the Ee and ee compositions. Observed differences between the hospital samples and the control were probably not simply because of selection but other factors like founder effect and genetic drift have certainly affected the gene frequencies in the populations studied.