An. sinensis is found in northeast India, Burma, Thailand, Malaysia, Indonesia, Kampuchea, Vietnam, China, Taiwan, Japan and Korea. In India it is reported from Meghalaya, Assam, and Mizoram. They are found in all types of environment including naturally-made clean water, stagnant or flowing. Their major habitats are rice fields, ditches, streams, irrigation canals, marshes, ponds, and ground pools. They mostly bite large animals, and human biting is relatively less when animals are present nearby. Their feeding takes place throughout the night from dusk to dawn, but heaviest biting occurs between 2 and 4 in the morning. Even though they are attracted by lights, they prefer to bite outdoor. They hibernate mostly under part of dense grasses during October–March. At the end of the hibernation period in March–April they feed during daytime. In August 1962 it was found that An. sinensis was a vector of vivax malaria in Korea. It has become one of the major vectors of vivax in China.
