| 1925 Australasian Championships | |
|---|---|
| Date | 24–30 January 1925 | 
| Edition | 18th | 
| Category | Grand Slam (ITF) | 
| Surface | Grass | 
| Location | Sydney, Australia | 
| Venue | White City Tennis Club | 
| Champions | |
| Men's singles | |
| Women's singles | |
| Men's doubles | |
| Women's doubles | |
| Mixed doubles | |
| Boys' singles | |
| Boys' doubles | |
The 1925 Australasian Championships was a tennis tournament that took place on outdoor Grass courts at the White City Tennis Club, Sydney, Australia from 24 January to 31 January. It was the 18th edition of the Australian Championships (now known as the Australian Open), the 4th held in Sydney, and the first Grand Slam tournament of the year. The singles titles were won by Australians James Anderson and Daphne Akhurst.
Finals
Men's singles
 James Anderson defeated 
 Gerald Patterson  11–9, 2–6, 6–2, 6–3
Women's singles
 Daphne Akhurst defeated 
 Esna Boyd 1–6, 8–6, 6–4
Men's doubles
 Pat O'Hara Wood / 
 Gerald Patterson defeated 
 James Anderson / 
 Fred Kalms 6–4, 9–7, 7–5
Women's doubles
 Daphne Akhurst / 
 Sylvia Harper defeated 
 Esna Boyd / 
 Kathleen Le Messurier 6–4, 6–3
Mixed doubles
 Daphne Akhurst / 
 Jim Willard defeated 
 Sylvia Harper / 
 Bob Schlesinger 6–4, 6–4