The hailstones measured in some cases over 10 centimeters in diameter and mainly hit an area near the city of Girona.
About fifty people were injured, of which 32 had to be treated in hospital in the small town of La Bisbal d'Empordà, several with head injuries.
The hailstorm was the strongest in the region of Catalonia in 20 years, reports El País, citing local authorities.
Material damage to roofs and cars was also reported by the emergency services.