The plant will be built in Yueyang city, close to the Changling and Baling refineries.
China plans to expand oil-processing capacity 25 percent by 2010 to meet rising consumption of gasoline, diesel and chemical raw materials.
The nation's oil demand will rise 6.8 percent to 7.6 million barrels a day this year, the International Energy Agency, an adviser to 26 oil-consuming nations, said in a forecast last month.
Officials with the planning department of Sinopec announced the preliminary plan for the project.
Sinopec is expanding a separate refinery in southern China in Guangxi province. The Guangxi government wants Sinopec to increase the annual capacity at the refinery to three million tonnes from 500,000 tonnes, Governor Lu Bing said. Sinopec has not decided on the scale of the revamp or the spending, spokesman Huang Wensheng said.
Sinopec may also build a refinery in the city of Lianyungang in the eastern province of Jiangsu, Qian Qilian, head of the Jiangsu Chamber of Commerce for the Petroleum Industry, said.
The refinery will be able to process 20 million tonnes of crude a year and may cost as much as 60 billion yuan (HK$61 billion), Qian said.
China may increase crude oil-processing capacity to 355 tonnes by 2010 from 285 million tonnes in 2005, the National Development and Reform Commission said last March.
And to meet growing demand for energy, China National Petroleum Corp, the nation's biggest oil producer, plans to spend 7 billion yuan on technology in the five years to 2010 to increase production.
The company will invest in 60 technology programs to provide support to its major operations, including oil exploration and the manufacture of drilling equipment, the state-run China Petroleum and Chemical Industry Association said.
China National, parent of Hong Kong-listed PetroChina (0857), said last month output from offshore fields may triple by 2010, helped by the discovery of new deposits in Bohai Bay.
Offshore output may rise to as much as five million tonnes a year of crude from 1.5 million tonnes last year, Shi Lin, president of China National's offshore engineering unit, said last month.
PetroChina has discovered oil and gas in the Jidong Nanpu oilfield in Bohai Bay with estimated reserves of 1.02 billion tonnes.