King Juan Carlos, who had an artificial hip implanted last November, will undergo an operation on his left hip, the Spanish royal family said.
The king has undergone a total of 13 operations in his lifetime, with many of his earlier operations being needed as the result of accidents that he suffered while participating in various sports.
It will be the second surgery for the king in recent months. In March, he had an operation on a sclerosis and a distal hernia, Xinhua reported Friday.
Recent weeks have witnessed the king's recovery slowing down. He showed signs of a lack of mobility in recent public appearances. He required to be steadied and prevented from falling at a recent event at the royal palace.
Prince Felipe of Asturias, the heir to the throne, will take over the King's official duties as he recovers from his latest intervention.