Pembroke's Dan Murray led a spirited Irish fightback but it was in vain as Zimbabwe edged the third youth ODI by two wickets to take an unassailable 3-0 lead in the five-match series.
Batting first, Ireland lost openers Freddie Ogilby and James West within the first eight balls of the innings and it took a breezy half century from Adam Leckey in a 69-run fourth wicket stand with Seb Dijkstra (24) to get the innings back on track.
Brendon Senzere (4-43) struck three times in an over to leave the visitors reeling at 115 for 7, but Murray shepheded the tail making a top score of 90 (8 fours, 1 six), adding 101 for the 8th and 9th wickets with Ollie Riley and Febin Manoj, both of whom made 17.
He missed out on a deserved century but a total of 235 gave the Irish attack hope of keeping the series very much alive.
Zimbabwe raced out of the traps as they put on 89 inside the powerplay for just one wicket.
Ireland fought back with two wickets apiece for Leckey, Dijkstra and Febin Manoj, but the hosts just did enough to clinch the win.
In a tight contest Pete Johnston and his support staff will reflect on the concession of 24 wides and 7 no-balls - rarely are games won with such efforts.
They have a chance to gain some consolation wins in the final two games on Thursday and Saturday in what has been a keenly contested series to date.