Mills, known for his work on BBC Radio 2, including Eurovision coverage since 2011, will no longer be involved in the contest, which will be held in Vienna in May.
Sara Cox, who has presented Radio 2's teatime show for the past seven years, will take over the role, according to reports. The Sun reported: 'Sara and Rylan have now been formally put forward to cover the event following Scott’s departure'.
Mills, in addition to commenting on the semi-finals on BBC One, also covered the final live on Radio 2 and broadcast his show from the hosting city for the week leading up to the event.