Video footage shows emergency services using a crane to winch one of the animals from the road in Pozo Canada, in the province of Albacete, as others wander loose on the road.
Civil Guard police tweeted a photo of a uniformed officer standing in front of two of the roving animals and wrote:
“Our Albacete traffic comrades today attending to some elephants who were victims of an accident in Pozo Canada (unfortunately one of the pachyderms died).”
The head of the government’s traffic department, Gregorio Serrano, said on Twitter early indications suggested the truck had overturned as it tried to overtake another vehicle.
The driver of the truck was not injured in the crash.
Authorities were forced to close the motorway to deal with the cleanup, causing major delays.
The local Pozo Canada council said on Twitter the remaining four elephants were being looked after until they could be safely transferred.