She attended primary school in Fore, County Westmeath and then the Loreto Convent in Mullingar.
For her results in the leaving certificate examination in 1913, she received a scholarship to attend University College Dublin (UCD).
She published her postgraduate work on St Patrick in Zeitschrift für Celtische Philologie (1926–1927), which was then published as the book Bethu Phátraic: the tripartite life of St Patrick in 1939.
She contributed essays to a number of volumes: Measgra i gcuimhne Mhichíl Uí Chléirigh (1944), Studies in early Irish law (1936), and The Book of Lecan: Leabhar Mór Mhic Fhir Bhisigh Leacain (1937).
Mulchrone died in her home on Patrick Street, Mullingar on 13 June 1973 and is buried in Ballyglass.