Dubai: An efficient all-round display saw a much improved Ireland post 160 for 6 and then restrict UAE to 136 for 7.
The Irish, who had failed to clear the ropes in their two previous games in the tournament, managed eight sixes. Kevin O'Brien, the top-scorer, hit three of those on his way to a quick-fire 40 from just 27 balls, while Paul Stirling (39) and Gary Wilson (26) hit two each.
Stirling dominated the early overs scoring 39 of the first 52 runs after both Stuart Poynter and William Porterfield fell cheaply.
The crucial stand for Ireland came from O'Brien and Wilson, who shared a fourth-wicket partnership of 53 in just 33 balls to shift the momentum decisively in Ireland's favour.
Greg Thompson (17) and Andy McBrine (14 not out) both chipped in as Ireland made its highest T20 total since June 2015.
Boyd Rankin (3 for 16) blew away any hopes the UAE entertained of chasing the total as he took three wickets in a fiery opening spell.
Further wickets for Craig Young and Kevin O'Brien reduced the home side to 21 for 5. Jacob Mulder, the legspinner, then got in on the action taking 2 for 20, as UAE struggled to 77 for 7.
A late surge from Amjad Javed, the captain, who clubbed five sixes in an entertaining unbeaten 47, made the match seem closer than it was. Javed added 59 runs in just 26 balls in an unbroken eighth-wicket stand with Mohammed Naveed (25 not out), but it was all too little, too late for his team.
Ireland won't know its semi-final opponent until Thursday, with The Netherlands, Scotland and Oman vying for the two semi-final slots from Group B.
Brief scores:
Ireland - 160 for 6 (O'Brien 40, Stirling 39, Javed 2-16, Zahoor 2-27)
UAE - 136 for 7 (Javed 47*, Rankin 3-16, Mulder 2-20)
Result - Ireland won by 24 runs