Elias Ismail was found guilty of fatally stabbing Hajar Hussein during a robbery and was executed in the Red Sea city of Jeddah, an interior ministry statement carried by the official SPA news agency said.
Most people put to death in Saudi Arabia are beheaded with a sword.
The executions so far this year include 47 for “terrorism” carried out in a single day on January 2.
In 2015, Saudi Arabia executed 153 people, most of them for drug trafficking or murder, according to an AFP count.
Human rights group Amnesty International says the number of executions in Saudi Arabia last year was the highest for two decades.
The kingdom is one of the world’s top executioners, although its tally in 2015 was far behind those of China and Iran.
Saudi Arabia has a strict Islamic legal code under which murder, drug trafficking, armed robbery, rape and apostasy are all punishable by death.