Rio Tinto said chief executive Sam Walsh would retire July 1, and would be succeeded by the global miner's copper and coal division head Jean-Sebastien Jacques.
The changeover comes as the miner faces the worst downturn to hit the sector in nearly two decades.
The world No.2 miner bowed to pressure from investors and credit rating agencies earlier this year and scrapped its payout policy, under which it promised never to cut its dividend from year to year, to better reflect commodity cycles.
"The board has decided that J-S is the right person to lead Rio Tinto in an increasingly complex world filled with both challenges and opportunities for our industry," Rio Tinto Chairman Jan du Plessis said on Thursday.
Walsh, a company veteran who joined Rio in 1991 after two decades in the auto industry, was appointed CEO in 2013 after the miner sacked its then-chief Tom Albanese over acquisitions that soured and prompted hefty writedowns.