Yiyang is a prefecture-level city located in the Hunan province of China. It is situated along the Zi River and straddles Lake Dongting, bordering the Hubei province to the north.
According to the 2010 Census, the city covers an area of 12,144 km² (4,689 sq mi) and has a population of 4,313,084 inhabitants. This represents a slight increase from the previous census in 2000, which recorded a population of 4,309,143.