Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi are the parasites that infect humans. Plasmodium falciparum and Plasmodium vivax cause most of the malarial infections worldwide. Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi are susceptible to chloroquine. Chloroquine was the world's most widely used antimalarial drug, but the most common and virulent parasite Plasmodium falciparum is now increasing resistance. Chloroquine-sensitive Plasmodium falciparum concentrates chloroquine to higher levels than did chloroquine-resistant parasite. Chloroquine concentrates in the highly acidic digestive vacuoles of susceptible Plasmodium parasites, where it binds to heme and disrupts its sequestration. Failure to inactivate or even enhanced toxicity of drug-heme complexes kill parasites via oxidative damage to membranes and digestive proteases. The loading dose of chloroquine in children is 10 mg/kg administered intravenously or by mouth and then three 5 mg/kg doses of chloroquine every 24 hours starting 6 hours after the loading dose should be given. Chloroquine is well absorbed, widely distributed in body tissues, slowly metabolized by the liver and very slowly cleared from the body. Residents in malaria endemic areas develop considerably immunity over time, but pregnancy makes women more vulnerable and infection during pregnancy increases the risk of anemia, miscarriage, stillbirth, and prematurity. The children are more vulnerable than adults to malaria infection. The aim of this study is to review the published data on the clinical pharmacology of chloroquine in children and their mothers.