India posted a competitive 185 for three riding on Virat Kohli's unbeaten 75, but their listless death bowling allowed Pakistan to overhaul the target with five balls to spare at the R Premadasa Stadium.
At one stage, the Pakistanis were in a spot of bother at 91 for five, but the dimimutive Akmal launched a fierce counter-attack and together with experienced Shoaib Malik added 95 runs off 50 just balls to see the side home.
For India, birthday boy Ravichandran Ashwin was the most successful bowler, scalping four wickets for 23 runs.
Earlier, Kohli celebrated his ICC ODI Player of the Year award with yet another sterling knock, while Sharma returned to form with a 40-ball 56 to power India to the challenging total.
The highlight of India's innings was the 127-run fourth-wicket partnership between Kohli and Sharma that came off just 77 balls.
Kohli decorated his 47-ball stay at the crease with seven fours and two huge hits over the fence, while Sharma struck six boundaries and two maximum during his knock.
Off-spinner Saeed Ajmal starred with the ball for Pakistan with figures of two 22 from his four overs.
Chasing the competitive total, Pakistan received twin blows in the fourth over in the form of opener Imran Nazir and young Nasir Jamshed.
In search of a big hit, Nazir skied a delivery from Ashwin to a running Suresh Raina at long-on. A ball later an unlucky Jamshed fell victim to an unnecessary mix up with his skipper Mohammad Hafeez as Pakistan slumped to 33 for two by the fourth over.Hafeez and wicket-keeper Kamran Akmal then joined hands and held fort for Pakistan with a 51-run stand.