Abstract: Under certain conditions the infection rate of the Anopheles stephensi to Plasmodium cynomolgi was 77±0.15%. The rhesus monkeys were fairly susceptible to the parasite infection. All monkeys were infected after being inoculated intravenously with more than 10⁵ sporozoites each. Test of current antimalarial drugs in this model showed that primaquine and pyrimethamine exhibited Causal prophylactic activity. Primaquine (2.5 mg (base)/kg×5 days) used in combination with chloroquine (20 mg (base)/kg×3 days) showed radical curative effect, while chloroquine exhibited only suppressive activity when used alone (20 mg(base)/kg×3 days).