Judge Paul Kelly handed down the sentence at a sitting of Carndonagh District Court.
The case was a family law case, so the parties cannot be identified.
The man had claimed he didn’t have any money.
But under cross-examination by a solicitor he admitted spending money on weekend events and going out.
He said he didn’t go to see his children because he didn’t have a car; and didn’t want to drive to see them in his tractor.
The solicitor then produced Facebook pictures – posted by the man himself on his own Facebook Page – showing the man out at sea fishing in recent weeks.
The solicitor said this left a huge question mark over the man’s claims that he didn’t have any money.
Judge Paul Kelly said he believed the man was hiding income from his ex partner and their children. He jailed the man for 14 days for non-payment of maintenance towards them.