A Democratic Republic of Congo commission is to review at least 60 mining contracts signed in the last decade, the government says.
Many Congolese work as illegal miners
Since March all negotiations on mining contracts have been suspended until the commission has finished its work.
DR Congo has vast mineral reserves, including gold, diamonds, 10% of the world's copper and more than a third of cobalt, used in mobile phones.
But few people have benefited and the wealth has attracted foreign looters.
The BBC's John James in Kinshasa says that since DR Congo's independence in 1960 its vast mineral wealth has been a key factor in the country's civil wars and instability.
After winning the country's first democratic elections in more than 40 years last year, the new government says it wants to make sure these resources are used for the benefit of its citizens.
Critics of President Joseph Kabila accuse him of agreeing deals with foreign mining companies which do not benefit local people.
The anti-corruption group, Global Witness, said it supported the decision to re-examine the contracts but said that if the process was to be credible, the government needed to ensure the highest standards of transparency and independence in the review process itself.
An earlier report by government consultants found some contracts lacked transparency, were signed without competitive bidding and made little attempt to get the best deal for the country.
Professor Peter Rosenblum from the US-based Carter Center is a consultant to the commission.
"The tragedy of the many tragedies in the Congo was that the people woke up after years of war and found that the family wealth had been given away, or sold off, or at least as far as people knew, it seemed to have just flitted away."
Vice-Minister for Mines Victor Kasongo says only six of the 60 mines are currently under operation.
He says that companies who have signed legitimate contracts will gain by having their contracts given more credibility.
"We want sustainability and also more than that we want development," he told the BBC.
The review is expected to take three months and could result in contracts being renegotiated.