The 1977 New South Wales Open, also known by its sponsored name Marlboro New South Wales Open, was a combined men's and women's tennis tournament played on outdoor grass courts at the White City Stadium in Sydney, Australia.

The men's was part of the 1977 Colgate-Palmolive Grand Prix circuit.

The singles titles were won by Evonne Goolagong Cawley and Roscoe Tanner.

Defending champion Tony Roche was unable to participate due to a stomach muscle injury.

[3][4][5] Roscoe Tanner defeated Brian Teacher 6–3, 3–6, 6–3, 6–7, 6–4 Evonne Goolagong Cawley defeated Sue Barker 6–2, 6–3 John Alexander / Phil Dent defeated Ray Ruffels / Allan Stone 7–6, 2–6, 6–3 Evonne Goolagong Cawley / Helen Gourlay Cawley defeated Mona Guerrant / Kerry Reid 6–0, 6–0