D
- Michael D'Arcy (born 1934): FG TD Wexford 1977–1987, 1989–1992, 1997–2002
- his son Michael W. D'Arcy (born 1970): FG TD Wexford 2007–2011, Senator 2011–
- Michael Davern (1900–1973): FF TD Tipperary South 1948–1965
- his son Don Davern (1935–1968): FF TD Tipperary South 1965–1968
- his son Noel Davern (born 1945): FF TD Tipperary South 1969–1981, 1987–2007, MEP Munster 1979–1984
- Michael Davitt (1846–1906): MP County Meath 1882, Anti-Parnellite MP North Meath 1892, Anti-Parnellite MP North East Cork Feb–May 1893, Anti-Parnellite MP South Mayo 1895–1899
- his son Robert Davitt (1899–1981): CnG TD Meath 1933–1937
- Dan Desmond (1913–1964): Lab TD Cork South–East, 1948–1964
- his wife Eileen Desmond (1932–2005): Lab TD Cork South–Central 1965–1987, MEP Munster 1979–1981
- Éamon de Valera (1882–1975): FF TD Clare 1919–1959, President 1959–1973, (also FF MP Parliament of Northern Ireland 1921–1937)
- his son Vivion de Valera (1910–1982): FF TD Dublin North–West 1944–1981
- his granddaughter Síle de Valera (born 1954): FF TD Dublin County Mid 1977–1981, Clare 1987–2007, MEP Dublin 1979–1984
- his grandson Éamon Ó Cuív (born 1950): FF Senator 1989–1992, FF TD Galway West 1992–
- Austin Deasy (born 1936): FG TD Waterford 1977–2002
- his son John Deasy (born 1967): FG TD Waterford 2002–
- James Devins (1873–1922): SF TD Sligo–Mayo East 1921–1922
- his grandson Jimmy Devins (born 1948): FF TD Sligo–North Leitrim 2002–2011
- John Dillon (1851–1927): IPP MP East Mayo 1880–1918
- his son James Dillon (1902–1986): NCP TD Donegal 1932–1937, FG TD Monaghan 1937–1969
- John Dinneen (1867–1942): FP TD Cork East 1922–1927
- his nephew Liam Ahern (1916–1974): FF Senator 1957–1973, FF TD Cork North–East 1973–1974
- Liam's son Michael Ahern (born 1949): FF TD Cork East 1982–2011
- his nephew Liam Ahern (1916–1974): FF Senator 1957–1973, FF TD Cork North–East 1973–1974
- Sir Maurice Dockrell (1850–1929): IUA MP Dublin Rathmines 1918–1922
- Maurice's son Henry Morgan Dockrell (1880–1955): FG TD Dublin County 1932–1948
- Henry's son Maurice E. Dockrell (1908–1986): FG TD Dublin South/Dublin South–Central/Dublin Central 1943–1977
- Henry's son Percy Dockrell (1914–1979): FG TD Dún Laoghaire 1951–1957, 1961–1977
- Maurice's son Henry Morgan Dockrell (1880–1955): FG TD Dublin County 1932–1948
- Michael Donnellan (1900–1964): CnaT TD Galway 1938–1964
- his son John Donnellan (born 1937): FG TD Galway 1964–1989
- James G. Douglas (1887–1954): Ind Senator 1922–1943, 1944–1954
- his son John Douglas (1912–1982): Ind Senator 1954–1957
Read more about this topic: Families In The Oireachtas