414 random samples of blood collected from unrelated male blood donors in Khartoum were analysed for erythrocytic glutathione reductase (GSR) phenotypes in relation to glucose-6-phosphate dehydrogenase (G6PD) and haemoglobin types by starch gel electrophoresis. The overall frequencies of GSR1 and GSR2 were found to be 0.9493 and 0.0507, respectively. The frequency of GSR° was very low (0.0241). The frequency of GSR2 was higher in G6PD-deficient subjects compared to normal subjects. GSR phenotypes were not related to the haemoglobin types. However, there was an excess of GSR° in subjects with haemoglobin A