The 35-year-old Irish actor is thought to have spent almost £3,000 over the years repairing the trouser accessory, which was given to him by his former footballer dad Eamonn.
A few weeks ago it went missing, and according to The Sun, Colin fears it may have been stolen and is desperate to get it back.
'Colin has had this lucky leather belt for so long he just can't bear to get rid of it. The thing is literally coming apart at the seams,' said a source.
'The belt has undergone numerous alterations, like having extra holes punched in it and extra leather added since he has gone through so many weight changes.'