The man, who has not been named, had been a top official with the Kuwait municipality
Kuwait’s supreme court on Sunday sentenced a top bureaucrat to 10 years in jail for joining and fighting with the Islamic State (IS) group in Syria and Iraq.
The court also fined the unnamed Kuwaiti national, who was a top official at the Kuwait municipality, $30,000 and convicted him of calling for other people to join the group.
The ruling is final and cannot be challenged.
Kuwaiti courts have sentenced a number of IS members, sympathisers and financiers to various jail terms.
A lower court in December sentenced a woman from the Philippines to 10 years in jail after convicting her of joining the group and plotting attacks.
Authorities in July said they had dismantled three IS cells plotting attacks, including a suicide bombing that hit a Shia mosque and another against an interior ministry target.
An IS-linked suicide bomber from Saudi Arabia killed 26 worshippers in June 2015 when he blew himself up in a mosque used by Kuwait’s Shia minority, in the worst such attack in the Gulf state’s history.