Four Saudi men were decapitated by sword in Najran in the south west of the country on Monday after being convicted of drug trafficking, the interior ministry said.
Brothers Hadi and Awad al-Motleq and their accomplices Mufarraj and Ali al-Yami were found to have smuggled "a large quantity of hashish" into the kingdom, the ministry said in a statement carried by the official SPA news agency.
The beheadings raise to 32 the number of executions announced in Saudi Arabia so far this year, according to an AFP tally.
Last year, there were 78 executions in Saudi Arabia and the UN High Commissioner for Human Rights denounced a "sharp increase in the use of capital punishment".
Rape, murder, apostasy, armed robbery and drug trafficking are all punishable by death under the kingdom's strict version of Islamic sharia law.