This move marks the second only appointment of a female chief executive to an Irish publicly listed company – the other is Anne Heraty at recruitment firm CPL Resources.
Glanbia’s current boss John Moloney is to retire after 12 years at the helm.
Ms Talbot has been with the company for over a decade and will take up her new position at the end of the year.
Siobhán is originally from Kilmoganny and is the daughter of the late Johnny and Moira Hickey. Her father, a farmer passed away over thirty years ago and her mother Maura taught at Tullahought National School and then at Windgap National School.