Beijing: Chinese astronauts have entered the country's orbiting space station for a month-long stay as China's sixth and longest crewed mission gets under way.

The Shenzhou-11 spacecraft that blasted off on Monday morning docked with the Tiangong-2 station on Wednesday using an automated manoeuvre worked out during missions to an earlier experimental station.

Having changed from his space suit into blue overalls, veteran mission commander Jing Haipeng opened the hatch and entered the station shortly after 6am Beijing time (9am AEDT), followed by astronaut Chen Dong, who is making his first journey into space, the official Xinhua News Agency reported.

"The two astronauts extended greetings to all the people of the nation in the space lab, and checked the status of the space complex," Xinhua said.