Abstract: The present paper reports on the result of an experimental study on the susceptibility of A. minimus and A. dims to two human Plasmodia: P. vivax and P. falciparum. 11 lots of A. minimus and A. dims were allowed to feed in vitro on the blood from 11 vivax malaria patients, and the feeding of the two species of mosquitoes was carried out simultaneously on one sample of blood. 10 lots of A. minimus became infected, the average gut and gland infection rate being 83.5% and 81.3% respectively, and the positive gland index 3.70. 11 lots of A. dims were all found infected, with an average gut infection rate of 88.2%, gland infection rate of 81.6% and a positive gland index of 2.98. Both species of the anophelines were shown to be highly susceptible to P vivax. So far as the gut and the gland infection rate was concerned, there was no significant difference in susceptibility between them. Although in most cases the number of oocysts on the stomach wall of A. dints apparently exceeded that of A. minimus, the mean diameter of differentiated oocysts of the latter was markedly larger and the intensity of the gland infection much higher. This probably indicated that A. minimus was a more appropriate host than A. dirus for the completion of the development of sporogonic cycle of P. vivax.Four lots of A. minimus and A. dirus were allowed to feed on the blood from 4 falciparum malaria patients. Three were successfully infected. The average gut infection rate of A. minimus and A. dirus was 65.8% and 66.2%, the oocyst index being 8.8 and 10.3 respectively; the average gland infection rate was 49.0% and 53.9%, and the positive gland index 2.31 and 2.46 respectively. These results showed high susceptibility to P. falciparum of the two anopheline species without any significant difference.The present study has experimently proved the high susceptibility of A. minimus to P. vivax and confirmed that in the mountainous areas of south China A. minimus is an important vector of the tertian malaria as well.