The unmanned Shenzhou 8 was launched at dawn and entered orbit successfully. It will travel 211 miles over 2 days to reach the Tiangong 1 module.
Tiangong translates to Heavenly Palace.
The chief designer of China’s manned space engineering project, Zhou Jianping, said: “Mastering the technology of rendezvous and docking will lay a firm foundation for China to build a space station.
“Once we have mastered this technology, we will possess the basic technology and capacity to build a space station, and this will open up possibilities for even larger activities in space.”
But Jianping added: “Since we have never conducted a similar test before and the system is so complicated, we have many unknowns.”
Dr Gregory Kulacki of the Union of Concerned Scientists said this was arguably China’s most important mission since its first manned space take-off in 2003.
“They are repeating things that the US and Soviet Union did 40 years ago. But it will give them the capability to complete their longstanding plans to have a Chinese-owned and occupied space station in lower Earth orbit by the beginning of the next decade.”
Russia, the US and other countries jointly run a 400 tonne International Space Station, but China does not belong to this group.
The US are not planning to test another manned rocket until 2017 and Russia said manned missions are not currently a priority either.
Engineers in China are working to create the right pressure and humidity so humans can live on a space station for a long stretches.
If they are successful, there will be two more expeditions to Tiangong 1. One of these will carry astronauts, including two women who will be the first to enter space for China.
China aims to have a fully-operating space station by around 2020.