At least 21 people have been injured and more than 120 buildings collapsed after a shallow earthquake struck the eastern province of Shandong on Sunday.

The 5.5-magnitude quake, near the city of Dezhou, happened just after 2:30am at a depth of 10 kilometres.

Online footage showed lights swinging, the ground shaking, and people evacuating their buildings.

The quake could be felt in cities as far away as Beijing and Tianjin, as well as Shanghai.

"The tremor was so strong... during the earthquake my head was shaking on the pillow, I thought I was having a nightmare," one person said on Weibo.

"I can't say anything except that it's scary," another netizen wrote.

State media said communication and power supplies had not been affected in the quake-stricken areas, but hundreds of train services had to be suspended.

Xinhua news agency added that the Ministry of Emergency Management has since dispatched a team to Shandong province to lead the rescue work. (Xinhua/AFP)