Jadeja finished with four for 29 to wreck Bangladesh to 173 all out in 49.1 overs at Dubai stadium.
Sharma then launched another assault on the bowlers during his 104-ball unbeaten knock which was studded with three sixes and five boundaries as India chased down the target in 36.2 overs.
Sharma put on 61 for the opening stand with Shikhar Dhawan (47-ball 40 with a six and four boundaries) before easing towards the target with another 64-run stand for the third with Mahendra Singh Dhoni who made 33.
It was another comfortable victory for the title holders who eased through their big match against Pakistan by eight wickets on Wednesday. The arch rivals meet again in the Super Four match in Dubai on Sunday.
Jadeja, playing his first one-day international for over a year, was at his best after India sent Bangladesh into bat on a flat pitch.
He only came into the squad as a replacement for all-rounder Hardik Pandya who was ruled out of the tournament with a back injury.
Pacemen Bhuvneshwar Kumar (3-32) and Jasprit Bumrah (3-37) were also ruthless as Bangladeshi batting couldn t get going with tail-ender Mehidy Hasan top-scoring with a 50-ball 42 with two sixes and two boundaries.
Bangladesh, who were bowled out for a mere 119 against Afghanistan on Thursday, were once again off to a disastrous start during which they lost half the side for just 65 runs.
Mushfiqur Rahman, who scored a brilliant hundred against Sri Lanka, managed 21 while star batsman Shakib Al Hasan failed yet again with 17.
It could have been worse had Mehidy not put on a fighting 66-run partnership for the eighth wicket with Mashrafe Mortaza who made 26 with two sixes.
Top two teams from the Super Four will play the final in Dubai on September 28.