The study was carried out to determine the antiplasmodial activity of seed oil of Moringa oleifera extracted using n-hexane solvent.
 Acute toxicity test was carried out on twelve albino mice grouped into 3 according to seed oil concentrations (250, 500 and 1000 mg/kg respectively) with each group having four mice. Thirty-five mice were infected with Plasmodium berghei and the mice were randomized into five groups of seven mice each (groups A, B, C, D and E) for antiplasmodial activity. Group A - negative control (non-treated), group B - positive control (chloroquine treated); group C (800 mg/kg), group D (400 mg/kg) and group E (200 mg/kg) of seed oil of Moringa oleifera. All groups were left untreated until after five days when 0.2 mL treatment dose for each group was administered. Treatment was carried out in four days and left for another five days for post treatment effect.
 The acute toxicity test showed that the seed oil of Moringa oleifera was safe and nontoxic to all mice. There was daily gradual reduction in PCV values; however group with the highest suppression of parasitemia had the highest PCV value after treatment. Group A as expected had the lowest PCV value of 22.23±1.98% which fell short of normal range (40 - 55%) and had its parasitemia load increased by 205% while in other groups, B, C, D and E the parasitemia had decreased by 100%, 97.02%, 90.48% and 67.65%respectively after treatment.
 Overall, the seed oil of M. oleifera at high concentrations showed a competitive parasite inhibition activity when compared with the result obtained in positive control group; however, few deaths recorded during and after treatment called for further investigation to determine its suitability for the treatment of malaria.