It is bounded by Cambodia, China, and Laos. It is in AEZ 3, characterized as warm humid tropics.
Climate varies from humid tropical in the southern lowlands to temperate in the northern highlands.
Destructive typhoons sometimes develop over the South China Sea during hot weather. Mean annual rainfall ranges from 1300 to 2300 mm. Rainfall is usually evenly distributed in June to October or November. October is the wettest month of the year. Total labor force is 35 million, with about 20 million engaged in agriculture.