The effectivity of intramuscular Delagil therapy with that of oral treatment in malaria patients are compared. On the basis of the therapeutic results of 8 malaria patients each it has been concluded that the cessation of fever and parasitaemia occur within a somewhat shorter time in the intramuscularly treated patients than in the orally treated ones. Finally, the usefulness of intramuscular Delagil therapy as an antimalarial medication has been assessed. According to the opinion of the author oral treatment has to be preferred in general in uncomplicated malaria cases. The indication fields of intramuscular Delagil therapy are the following: 1. Unconsciousness, cerebral or other complications. 2. High fever, poor general condition requiring rapid action; in the latter two cases the above-mentioned frequent application of lower doses is recommended. 3. Relatively good general condition but abundant vomiting and/or diarrhoea.