Giannaioi () is a community of the municipal unit of Falaisia in Arcadia, Peloponnese, Greece. It consists of the two mountain villages Ano Giannaioi and Kato Giannaioi. 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.