The latest execution in the western city of Taif brings to 142 the total number of death sentences carried out in the kingdom this year compared with 87 in all of 2014, according to AFP tallies.
Saad bin Marzooq al-Subaie killed Hamad bin Mohammed al-Subaie by running him over with his car following a dispute, said the ministry's statement published on the official SPA news agency.
Saudi executions are usually carried out by beheading with a sword.
London-based Amnesty International says Saudi Arabia had the world's third-highest number of executions last year, far behind China and Iran, but ahead of Iraq and the United States.
Under the kingdom's strict Islamic legal code, murder, drug trafficking, armed robbery, rape and apostasy are all punishable by death.