The accident happened late on Saturday at a mine operated by Vang Danh Coal Company, a unit of Vietnam's state coal miner Vinacomin, Reuters reported citing the state-run Thanh Nien newspaper on Sunday.
A rescue team pulled out the bodies of four miners, it said.
The newspaper did not give a reason for the collapse. In March a similar accident happened at a Vang Danh-operated mine but no one was killed.
AMK/PR