Prokhorov heads the Onexim investment group, a major shareholder in Polyus Gold. The previous Polyus chairman was Sergei Batekhin, deputy director general of Interros holding.
"The board also decided to terminate the powers of Polyus Gold general director Pavel Skitovich ahead of time, and appoint Polyus Gold board member Yevgeny Ivanov as company general director," the statement said.
The company statement quoted Prokhorov as saying: "I am convinced that Polyus Gold has huge development potential. To use the company's existing capabilities to the maximum and ensure the strongest possible growth in shareholder value, in the interests of all shareholders, I decided to personally head the board," he said.
Prokhorov and another Russian oligarch, Vladimir Potanin, are currently dividing the Interros managing company and each holds a 22% stake in Polyus Gold, whose market capitalization is currently around $7.7 billion.
Polyus Gold said in September it had become the world's fourth largest gold miner, with 2,100 metric tons of proven and probable gold reserves. The company's asset portfolio comprises ore and placer deposits in the Krasnoyarsk Territory, the Irkutsk, Magadan and Amur regions and Yakutia.
The company's gold production in 2006 was 1.2 million troy ounces. Net profit calculated to International Financial Reporting Standards was $1.16 billion in 2006, or 930% more than in 2005, with earnings at $735 million, representing 55% year-on-year growth.