Harmanpreet smashed 52 off 34 balls with eight fours and a six while opener Shafali Verma played an attacking knock of 48 off 33 balls.
Smriti Mandhana (25 off 17 balls) also started well but couldn’t convert that into a substantial knock.
Left-arm spinner Jess Jonassen (4/22) was the pick of the Australian bowlers.
Australia overhauled the target of 155 with an over to spare.
Ashleigh Gardner top-scored for Australia with a 35-ball 52 not out.
For India, Renuka Singh grabbed four wickets for 18 runs, while Deepti Sharma took two wickets. Meghna Singh got one wicket.
Brief scores:
India: 154/8 in 20 overs (Harmanpreet Kaur 52, Shafali Verma 48, Jess Jonassen 4/22).
Australia: 157 for 7 in 20 overs (Ashleigh Gardner 52 not out; Renuka Singh 4/18, Deepti Sharma 2/24).
