The launch of Shenzhou VI is scheduled for 11am at Jiuquan Satellite Launch Base, in the Gobi desert in northern China, with the mission lasting 119 hours if all goes according to plan, the state-run China News Service reported on Sunday.
It said midday was chosen as the launch time to improve safety and allow launch personnel enough time for final preparations, unlike some past unmanned missions that pushed off in the night and predawn hours.
"The main reason is to provide greater safety for the astronauts because these spaceships are manned spaceships," the report said.
The military-backed space programme is a major prestige project for the communist government. China has announced plans to land an unmanned probe on the moon by 2010 as well as operate a space station.
China's first manned space flight in October 2003 made it the third country able to launch a human into space on its own, after Russia and the United States.
Colonel Yang Liwei, a former fighter pilot, orbited the Earth for 21 and a half hours aboard the Shenzhou V capsule before landing in China's northern grasslands.
Earlier reports said he would not be making this trip.
Training fighter pilots
Instead, Yang is helping train former fighter pilots who are reportedly the candidates for Shenzhou VI. The initial group of 14 has been narrowed down to three pairs, or a total of six, the China News Service said.
It said Zhai Zhigang and Nie Haisheng, two alternates for Shenzhou V, were "the strongest group with the greatest confidence" for carrying out the mission.
Yang Liwei will help train
candidates for Shenzhou VI
Plans call for the capsule to carry two astronauts - or "taikonauts" for the Chinese word for space.
Beijing does not participate in the US-led international space station project.
The report cited an unnamed researcher as saying that the new space capsule was not a duplicate of Shenzhou V due to more than 100 technological modifications that made it more conducive to scientific research.