A further two people were seriously injured in the blaze at the residence in the town of Villafranca de Ebro in Zaragoza, according to the Spanish news website Diario Sur.
They remain in a critical condition, while several others received treatment for smoke inhalation.
Firefighters were alerted to the blaze at the residence – the Jardines de Villafranca – at 5am (4am UK time) on Friday.
Those who were killed in the fire died from smoke inhalation, Spanish newspaper Heraldo reported. The residence is home to 82 elderly residents.
The blaze started in one of the rooms, Fernando Beltran, the national government’s top official in the region, told reporters. All of the victims were elderly residents, he added.
Fire crews, paramedics and police officers remain on site, said a spokesperson for the regional government of Aragon who confirmed the fatalities.
It took firefighters several hours to extinguish the blaze, they said. The cause of the fire is unknown and is being investigated
