- GOUGE, THOMAS (1605? - 1681), Nonconformist divine and philanthropist
- GOUGH, JETHRO (1903 - 1979), Professor of pathology
- GOUGH, MATHAU - see GOUGH, MATHEW
- GOUGH, MATHEW (c. 1390 - 1450), soldier
- GOULD MORGAN, Sir CHARLES (d. 1806), M.P. - see MORGAN
- GOULD, ARTHUR JOSEPH (1864 - 1919), Rugby footballer
- GOULD, Sir CHARLES (d. 1806), M.P. - see MORGAN
- GOULD, ROBERT (1864? - 1932), rugby footballer - see GOULD, ARTHUR JOSEPH
- GOWER, Sir ERASMUS (1742 - 1814), admiral
- GOWER, HENRY (1278? - 1347), bishop
- GOWER, HERBERT RAYMOND (1916 - 1989), Conservative politician
- GRANVILLE-WEST of PONTYPOOL, Baron - see WEST, DANIEL GRANVILLE
- GRAVELL, DAVID (1787 - 1872), farmer, herbalist, and publisher
- GRAY, - see GREY
- GRAY, RHYS (fl. 1661-1672), poet
- GRAY, THOMAS (1847 - 1924), mining engineer and local historian
- GRAY, THOMAS - see GREY, THOMAS
- GREEN, BEATRICE (1894 - 1927), political activist
- GREEN, CHARLES ALFRED HOWELL (1864 - 1944), second Archbishop of Wales
- GREEN, FRANCIS (1854 - 1942), antiquary
- GREENLY, EDWARD (1861 - 1951), geologist
- GREGORY, HENRY (1637? - 1700?), preacher with the Arminian Baptists
- GRENFELL family, Swansea industrialists
- GRENFELL, DAVID RHYS (1881 - 1968), Labour politician
- GRESHAM, COLIN ALASTAIR (1913 - 1989), archaeologist, historian and author
- GREVILLE, CHARLES FRANCIS (1749 - 1809), founder of Milford Haven town, Pembrokeshire
- GREVILLE, ROBERT FULKE (1800 - 1867) - see GREVILLE, CHARLES FRANCIS
- GREVILLE, ROBERT FULKE (1751 - 1824) - see GREVILLE, CHARLES FRANCIS
- GREY family (POWIS, lords of),
- GREY, THOMAS (1733 - 1810), Independent minister
- GRIDLEY, JOHN CRANDON (1904 - 1968), industrialist
- GRIFFITH family Cefn Amwlch, Penllech, Llŷn
- GRIFFITH family Carreg-lwyd,
- GRIFFITH, SIDNEY (d. 1752), Methodist and associate of Howel Harris
- GRIFFITH family Garn, Plasnewydd,
- GRIFFITH family PENRHYN,
- GRIFFITH, Tanybwlch Maentwrog - see EVANS
- GRIFFITH, ALEXANDER (d. 1676), cleric and controversialist
- GRIFFITH, ALICE (1730 - 1808), Moravian - see GRIFFITH, WILLIAM
- GRIFFITH, DAVID (1792 or 1794 - 1873), Independent minister
- GRIFFITH(S), DAVID (1726 - 1816), cleric and schoolmaster
- GRIFFITH, DAVID (Clwydfardd; 1800 - 1894), eisteddfodic bard and arch-druid
- GRIFFITH, DAVID (1841 - 1910), schoolmaster, cleric, and diarist
- GRIFFITH, DAVID (1823 - 1913), Independent minister - see GRIFFITH, DAVID
- GRIFFITH, DAVID - see GRIFFITHS, DAVID
- GRIFFITH, EDMUND (1570 - 1637), bishop
- GRIFFITH, EDMUND (1559 - 1617), rector - see GRIFFITH, EDMUND
- GRIFFITH, EDWARD (1832 - 1918), antiquary
- GRIFFITH, ELIZABETH (1727 - 1793), author
- GRIFFITH, ELLIS JONES - see ELLIS-GRIFFITH, Sir ELLIS JONES