One hundred and ninety-two male malaria patients admitted to two different hospitals within 1 year, were studied. There were 74 malaria cases with glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and 118 G-6-PD normal malaria cases, randomly selected as a control group. History of dark urine, and the presence of jaundice, haematocrit, total bilirubin and parasite count on day of admission were not significantly different comparing both groups. The number of observed complications did not differ either. Distinctions were detected in abnormal symptoms and in some laboratory parameters in patients with Plasmodium falciparum infection. G-6-PD deficient patients had significantly less gastrointestinal disturbances (P = 0.006), higher serum glutamic oxalacetic transaminase (P = 0.009) and significantly lower blood urea nitrogen (P = 0.007) when compared with the control group. These findings indicate that G-6-PD deficiency when the variants are aggregated, in male adult patients has no significant influence on the clinical presentation of malaria.