He replaces the current managing director of UPM-Kymmene, Kevin Lyden, who will retire on 14 September this year. Lyden ranked number 45 in PrintWeek's latest Power 100.
Oldham will be based in London and will start his role on 1 July. He was previously business general manager for International Paper's European papers division.
He has also been sales and marketing director for International Paper, managing director for Scholastic Book Fairs UK, and has held senior roles with the Robert Horne Group.
Lyden said: "We are pleased to welcome Will to UPM. He brings to the role a wealth of senior experience and knowledge."
Oldham added: "The industry faces major change, I see UPM as one of the strongest global forestry product businesses, and I look forward to the challenges and opportunities ahead."
The company's main products are printing papers, label materials and wood products, and in the UK it operates two paper mills.
UPM Shotton in Deeside North Wales produces 100% recycled newsprint for the UK and international markets.
Its Caledonian site in Ayrshire, Scotland, produces lightweight coated paper for the UK and international magazine publishing markets.
