Abdullah bin Mashari was executed for shooting dead Mansour al Kharir following an argument caused by "family differences", the ministry said in a statement carried by the official SPA news agency.
It was the third execution announced in Saudi Arabia this year, after a record 153 people were put to death in 2007. That figure compared with 37 beheaded in 2006, and the previous record number of 113 executions in 2000.
Rape, murder, apostasy, armed robbery and drug trafficking can all carry the death penalty in the ultra-conservative Gulf country, where executions are usually carried out in public.
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