A review of the Greek members of the Temnothorax graecus species-group revealed two species new to science: T. mytilenes sp. nov. (Greece: Lesbos, Samos, Kos and Rhodes, and Türkiye: Ayvalık Peninsula) and T. phaetoni sp. nov. (endemic to Cyclades). Additionally, the diagnoses and redescriptions are provided for T. aeolius (Forel, 1911), T. graecus (Forel, 1911), and T. smyrnensis (Forel, 1911). Lectotypes are designated for Leptothorax bulgaricus subsp. graecus Forel, 1911, Leptothorax bulgaricus subsp. aeolius Forel, 1911, and Leptothorax bulgaricus subsp. smyrnensis Forel, 1911. All members of the graecus species-group are associated mostly with moderately humid to arid deciduous forests or Mediterranean bushes. A dichotomous key to the graecus species-group from Greece is given.