Lady Di is a diminutive of Lady Diana Spencer, later Princess of Wales (1961–1997).
Lady Di may also refer to:
- People
- Lady Diana Beauclerk (1734–1808), otherwise known as "Lady Di", English noblewoman
- Dianne Walker (b.1951), known as "Lady Di", American tap dancer
- Dianna Agron, nicknamed "Lady Di" in some media, American actress
- Fictional characters
- Lady Diana Sartoris, in The Whip (play) (1909), deputy of the Beverly Hunt
- Lady Di (EastEnders), a pet bulldog in the BBC soap opera EastEnders
- Lady Di, in Sir Cumference books, wife of the title character
- Lady Di, in Carandiru (film) (2003), trans woman played by Rodrigo Santoro
- Lady Di, in The Zero Hour (2010 film), played by Amanda Key
- Music
- "Lady Di", composition by guitarist Jim Ferguson
- "Lady Di", second place song in Melodi Grand Prix 1982
- Other
- Lady Di, a 1953 NZR DSA class locomotive, withdrawn in 1984
- The "Lady Di", a pink variant of the tricorne hat
- The "Lady Di", 1980s pageboy women's hairstyle
See also
- Di (disambiguation)
- Lady Dai or Xin Zhui (c. 217 BC–168 or 169 BC), Chinese noblewoman