Awad Rawili stabbed to death Jazaa Rawili, a relative, during an argument , said the statement carried by the official SPA news agency.
He was executed in the northern city of Araar.
His beheading brings to 39 the number of people executed in Saudi Arabia since the beginning of the year, according to an AFP tally.
In 2012, the kingdom executed 76 people, according to an AFP tally based on official figures. Human Rights Watch has put the number at 69.