Shami has not played for India since the World Cup last year due to a knee injury. He was picked in the limited-overs squads for the tour of Australia last month, but was withdrawn due to a hamstring injury.
Negi, who has been picked for the three-match T20I series against Sri Lanka starting next week, has retained his place.
Virat Kohli, rested against Sri Lanka, returns as expected.
Negi has the experience of playing T20 cricket with the likes of MS Dhoni, Suresh Raina, R Ashwin, Ravindra Jadeja and Ashish Nehra, having played key roles for Chennai Super Kings in the Indian Premier League after he joined the side in 2014. He has 479 runs at a strike-rate of 134.92 and 46 wickets at an economy of 7.42 from 56 T20 matches and was in fine form in the recently concluded Syed Mushtaq Ali tournament.
Dhoni, as expected, will lead the squad. The senior trio of Yuvraj Singh, Harbhajan Singh and Ashish Nehra also keep their places.
The 16-team ICC World T20 will be played in three stages from .
India are placed in Super 10 Group 2 along with Pakistan, Australia, New Zealand and a qualifier from the group stage. India begin their campaign against New Zealand in Nagpur on and face Pakistan in Dharamsala on .
MS Dhoni (capt, wk), Shikhar Dhawan, Rohit Sharma, Virat Kohli, Ajinkya Rahane, Yuvraj Singh, Suresh Raina, R Ashwin, Ravindra Jadeja, Mohammed Shami, Harbhajan Singh, Jasprit Bumrah, Pawan Negi, Ashish Nehra, Hardik Pandya.
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