Fire crews worked overnight to prevent the flames from spreading to residential areas in the region of Gortynia in the Peloponnese.
Fires continued to rage in largely inaccessible terrain close to the areas of Fanaraki, Kastraki, Pyrri, Lotus, Liodora, Chrysochori and Dafni.
The blazes have destroyed large areas of farm land and several animal barns, while disrupting electrical power and water supply.
Authorities on Tuesday evacuated 21 villages as a precaution: Chrysochori, Iamatiges Piges, Loutra, Litharos, Ayioneri, Parnassos, Ochthia, Aetorachi, Kalliani, Doxa, Toubitsi, Melidoni, Palaiochori, Pyrris, Agios Ioannis, Lotus, Liodora, Kastraki, Fanaraki, Livadaki and Kapellitsa.
Reinforcements were expected on Wednesday to help the fire fighting effort.