The year-long brief was awarded following a competitive pitch.
Inkling will create a calendar of activity to support the attraction's key trading periods throughout the year including Christmas, Easter, summer and Halloween as well as ongoing press office activity.
The account will be led by Inkling partner Jono Marcus and the agency will report to The O2 comms manager Stephanie Moses.
The O2 comms director Jeremy King said: "We were very impressed with the strategy, thinking and ideas presented by Inkling during the pitch. We felt it perfectly captured the essence of Up at The O2, and most importantly will continue to develop its standing as a premier London visitor attraction and experience to a variety of audiences."
Inkling was awarded the business following a pitch that outlined key stand-out activities for the brand and creative press office as well as a strong emphasis on broadcast media.