The councillor in charge of agriculture in Andalucia's regional government, Isaias Perez Saldana, told a news conference the disease could spread to the southwestern region of Extremadura and the central region of Castile-La Mancha.
Rules restricting the movement of livestock in the affected farms, as well as in farms found within a 20 kilometre (12 mile) radius, would be "rigourously applied," he said.
Bluetongue affects affects ruminants -- animals such as cows and sheep which chew the cud -- but not humans.
It is transmitted by insects and causes high fevers, mouth ulcers, swollen heads and turns an infected animal's tongue blue.
The disease has hit livestock in The Netherlands, Germany, Belgium and northern France in the past year after previously being confined to countries on the Mediterranean basin.