- BRWMFFILD, MATTHEW (fl. 1520-60), poet
- BRYAN, JOHN (1776 - 1856), Wesleyan Methodist minister
- BRYAN, ROBERT (1858 - 1920), poet and composer
- BRYANT, JOHN (Alawydd Glan Tâf; 1832 - 1926), harpist
- BRYANT, TOM (1882 - 1946), harpist
- BRYCHAN (fl. mid 5th century), saint
- BRYCHAN - see DAVIES, JOHN
- BRYDGES, Sir HARFORD JONES (1764 - 1847), diplomatist and author
- BRYFDIR - see JONES, HUMPHREY
- BRYN-JONES, DELME (1934 - 2001), opera singer
- BRYNACH (fl. late 5th century - early 6th century), saint
- BRYNFAB - see WILLIAMS, THOMAS
- BRYNMOR-JONES, DAVID BRYNMOR - see JONES, DAVID BRYNMOR
- BRYTHONYDD - see WILLIAMS, DAVID PRYSE
- BUCKLAND, 1st Baron (1877 - 1928) - see BERRY
- BUDDUG - see PRYSE, ROBERT JOHN
- BULKELEY family
- BULKELEY, FRANCIS Penmynydd (d. 1722) - see TUDOR
- BULKELEY, HUGH (fl. 17th century), bard
- BULKELEY, RICHARD (fl. late 16th - early 17th century), bard
- BULKELEY, WILLIAM (1691 - 1760), squire and diarist
- BULKELEY-OWEN, FANNY MARY KATHERINE (1845 - 1927), author
- BULMER, JOHN (1784 - 1857), Independent minister
- BULMER-THOMAS, IVOR (1905 - 1993), Labour, later Conservative, politician and writer
- BURGESS, THOMAS (1756 - 1837), bishop
- BURTON, IAN HAMILTON (Archimandrite Barnabas) (1915 - 1996), Orthodox priest
- BURTON, PHILIP HENRY (1904 - 1995), teacher, writer, radio producer and theatre director
- BURTON, RICHARD (1925 - 1984), stage and film actor
- BURTON, URIAH, 'Big Just' (c.1926 - 1986), bare-knuckle fighter and activist
- BUSH, PERCY FRANK (1879 - 1955), rugby player
- BUTE family (marquesses of Bute, Cardiff Castle, etc.),
- BUTLER, Dunraven - see EDWIN
- BUTLER, Lady ELEANOR CHARLOTTE (1739 - 1829), one of the 'Ladies of Llangollen'
- BUTLER, FRANCES ANNE (1809 - 1893), actress - see KEMBLE, CHARLES
- BUTTON, Sir THOMAS (d. April 1634), admiral and explorer
- BWTTING, RHYS (fl. 15th century), harpist
- BYCHEINSHA, WILLIAM (fl. 1584-1617), poet - see BIRCHINSHAW, WILLIAM
- BYRCHINSHA, WILLIAM (fl. 1584-1617), poet - see BIRCHINSHAW, WILLIAM