Mohammad Hafeez's unbeaten century ensured the tourists defied four rain delays to post a testing target in a match reduced to 47 overs by the weather.
Hafeez struck 122 from 113 balls and combined in a 188-run stand with Asad Shafiq, whose 84 was his best return in an ODI.
Late hitting from Kamran Akmal, who spent two seasons in Irish domestic cricket a decade ago, helped Pakistan reach 266 for five - a total improved to 275 on the Duckworth-Lewis Method because of the rain.
Kevin O'Brien's two for 43 was the best of the Irish figures, although the all-rounder went at 8.60 an over after allowing Hafeez and Shafiq to up the tempo after the tourists had begun at a crawl.
- Sports & Recreation
- Mohammad Hafeez
- Asad Shafiq
- Kamran Akmal