Deepti Sharma picked up figures of 4-10 while Shafali Verma smashed her second consecutive half century, helping India to a comfortable 10-wicket win.
India Women vs South Africa Women: Indian spinners Deepti Sharma and Radha Yadav bowled brilliantly and restricted South Africa to 98/8 in 20 overs.
India women vs South Africa women: The next match of the series will be played at the same venue on September 29.
India women: Harmanpreet Kaur heaped praise on bowlers, led by Deepti Sharma, as they defended a modest total of 130 runs to win the first T20I in Surat.
India Women vs South Africa Women: Deepti Sharma bowled three maiden overs in her four-over quota and picked up three wickets, conceding just eight runs.
Deepti Sharma gave Velocity a last-minute scare but the partnership between Danielle Wyatt and Mithali Sharma was enough to take them over the line.
England lost their final seven wickets for 25 runs to be bowled out for 136.
Indian women's team will play a three-match ODI series at home against England, starting February 22.
The White Ferns chased down the target in 29.2 overs to register a morale-boosting win.
While India skipper Mithali Raj was selected to lead the World Cup team, Harmanpreet Kaur and Deepti Sharma were also included.
The India women's team will play hosts England in the final of the ICC Women's World Cup at Lord's on Sunday.