Hanna has vast corporate experience having held senior company roles for the last 35 years.
His current roles are as chairman at equipment supplier Aggreko and Arena Events.
Previously Hanna has held executive positions at Cadbury, Inchcape and Dalgety.
Interserve said his appointment “reflects a renewed focus on growth opportunities across the UK and international markets of the equipment services division.”
Alan Lovell, Chairman, Interserve Group, said: “We are very pleased to welcome Ken to Interserve. His wide-ranging senior management and boardroom experience will be a great asset to our Board.
“Ken’s appointment will also provide valuable counsel for RMD Kwikform, working with the team to ensure it continues to be the leading engineering solutions provider of specialised temporary structures helping to deliver major infrastructure and building projects around the world.”
Interserve was forced into a pre-pack administration earlier this year by mounting debts.
RMD Kwikform has been the strongest performing part of the business but 2018 results showed a 27% drop in operating profits to £39.6m as turnover fell to £195.5m from £229m.