Yuvraj Singh holds the record for the fastest 50 for India in T20 internationals, having scored it in 12 balls against England. Abhishek Sharma gets second place on the list, scoring a 14 ball fifty against New Zealand while Shivam Dube slammed a fifty in 15 balls against New Zealand. 

List of Fastest 50 for India in T20 Internationals

Yuvraj Singh- 12 balls vs England

Abhishek Sharma- 14 balls vs New Zealand

Shivam Dube- 15 balls vs New Zealand

Hardik Pandya- 16 balls vs South Africa

Abhshek Sharmna- 17 balls vs England