Rio Tinto has picked its new chairman.

After a nine-month search, Rio Tinto says former investment banker Simon Thompson will succeed Jan du Plessis, who has been the mining giant's chairman since 2008.

Far from an outsider, Mr Thompson is currently chairs Rio’s remuneration committee, and joined the company's board as a non-executive director in 2014.

“Mr Thompson has over 20 years' experience working across five continents in the mining and metals industry,” Rio Tinto said in a statement.

He has held senior positions at Anglo-American, AngloGold Ashanti, Rusal and Newmont Mining Corp.

He also chaired multinational private equity firm 3i Group and Tullow Oil, a British oil and gas exploration company operating largely in Africa.

Mr Thompson began his career at British investment banks SG Warburg (now part of Swiss-based UBS), and N M Rothschild (controlled by the Rothschild family).

“I look forward to leading the board as we work with J-S [Jean Sebastien-Jacques] and his team to ensure that Rio Tinto continues to deliver superior returns for its shareholders by maintaining its capital discipline and 'value-over-volume' approach,” Mr Thompson said.

Some believe Mr Thompson has been handed a bag he may not want to hold, with upcoming fraud charges against Rio from the US corporate regulator.

The Securities and Exchange Commission alleges Rio Tinto tried to cover up more than $US3 billion worth of losses on a failed coal investment in Mozambique in 2011.

Rio is also under investigation by the UK Serious Fraud Office for “suspected corruption in the conduct of business in the Republic of Guinea”.