Katherine, Katharine, Kathryn or Kathy Williams may refer to:
- Katharine Isabella Williams (1848–1917), British chemist
- Kath Williams (1895–1975), Australian women's activist
- Katharine Williams, Australian judge
- Kathryn Williams (born 1974), English singer-songwriter
- Kathy Williams, a character in The Fog
See also
edit- Catharine R. Williams (1787–1872), American writer and suffragist
- Catherine G. Williams (1914–2020), American social worker
- Kathryn Harby-Williams (born 1969), Australian netball player and television presenter
- Katherine Dienes (born 1970), also known as Katherine Dienes-Williams, a New Zealand-born organist and conductor