Bangladesh will face West Indies in the Tri-Series final after beating them by five wickets in Malahide.
Ireland's hopes of reaching the final were ended by the result and the tournament hosts now face Bangladesh in a dead-rubber on Wednesday.
Both Mushfiqur Rahim (63) and Soumya Sarkar (54) hit half-centuries as Bangladesh eased to their total of 248 to win by five wickets with 16 balls to spare.
West Indies batted first but there was insufficient back-up for the knocks of Shai Hope (87) and Jason Holder (62) and, having now lost twice to Bangladesh in a week, they will be hoping for retribution in Friday's final.
