This paper reported the vectorial capacity of various anopheles in a tertian malaria infectious area for the period of 1980-1982. The ecological data of various anopheles, which used to take the account into vectorial capacity, were collected in the same manner. We consider that whatever species of anopheles possessing the biggest vectorial capacity, should also be probably the principal vector in that area. 13 species of anopheles had been found in the investigation region but only four species could provide enough data to be involved in the vectorial capacity. The A. sinensis became the highest. Reviewing the monthly distribution, this species as vectorial capacity showed a positive correlation with malaria incidence rate. Therefore this is regarded as the principal vector in that area.