Pat O'Hara Wood defeated Ronald Thomas 6–3, 4–6, 6–8, 6–1, 6–3 in the final to win the men's singles tennis title at the 1920 Australasian Championships.

Draw

Key Q = Qualifier WC = Wild card LL = Lucky loser r = Retired

Top half

Bottom half

External links Grand Slam Tennis Archive – Australasian Open 1920