Venue management company SMG was chosen by Aberdeen City Council's finance, policy and resources committee.
An SMG spokesperson said the project would become a "jewel in the crown" of the city and the wider north-east economy.
Plans for the new AECC were approved last year.
Council leader Jenny Laing said: "I am looking forward to hearing about the exciting plans which SMG has for operating the new venue in the future."
The council said it should be stressed that jobs at the current and new AECC would remain as they are currently under Transfer of Undertakings (Protection of Employment) regulations (TUPE).
The preferred bidder for the operator for the new Aberdeen Exhibition and Conference Centre (AECC) has been selected.