Travis Head kept Australia in the hunt with a blistering 76 off 43 balls, but his teammates choked against spinners Kuldeep Yadav (2-24) and Axar Patel (1-21) to be restricted at 181-7.
India closed out the Super Eight with three wins from three matches, and will take on Group 2 runner-up England in the second semifinal on Thursday.
Unbeaten South Africa, which topped Group 2 with three out of three, won’t know its semifinal opponent until the last Super Eight game later Monday between Afghanistan and Bangladesh.
Australia was in danger of missing out on the semifinals.
