Giannaioi (Greek: Γιανναίοι) is a community of the municipal unit of Falaisia in Arcadia, Peloponnese, Greece. It consists of the two mountain villages Ano Giannaioi (population 23 in 2001) and Kato Giannaioi (population 66 in 2001). Ano Giannaioi is 1 km southeast of Kato Giannaioi. Both villages are situated on a mountain slope, in the northern foothills of the Taygetus mountains, between 600 and 700 m elevation. Kato Giannaioi is 1 km south of Kamara, 5 km north of Dyrrachio, 11 km southeast of Leontari and 19 km south of Megalopoli. The area was severely damaged in the August 2007 Greek forest fires.