Oxidative stress has been suggested to be implicated in malaria. But it is not clear whether its major role is to kill intraerythrocytic parasites or to cause damage to host tissues. We have studied it in 24 European subjects hospitalized in Saint-André hospital, Bordeaux, France for Plasmodium falciparum access returning from a tropical trip, and in a group control of 16 subjects. Malondialdehyde, one of the oxidative stress markers is significantly increased in patients compared to the control group (m = 5.24 vs 2.14 mol/l). At the same time, it is observed a significative decrease in antioxidant factors, vitamin A and vitamin E. We found no relationship of the severity of malaria to the importance of the oxidative stress, and the question whether the oxidative stress attack host tissues or kill parasites remains entire. These observations should be completed by larger studies, particularly to improve malaria treatments available nowadays.