Henry Hennessy 1849-1855

Matthias O'Keeffe 1856-1875

Richard Caulfield 1875-1887

Owen O'Ryan 1888-1895

William F. Butler 1896-1900

John Fawcett 1910-1930

T.A. Conroy 1932-1952 - Prof. Alfred O'Rahilly was 'honorary director' of the Library during part of this period

Daniel O'Keeffe 1959-1972

Patrick J. Quigg 1973-1986

Alasdair T. Paterson (acting)

Thomas J.A. Crawshaw 1991-1994

John Fitzgerald 1995-30/9/2022 - Colette McKenna was Director of Library Services during part of this period ending 30/6/2022

Coral Black 11/4/2023-