In a match reduced to 40-over-a-side because of rain, Butt (70 off 84) and Yousuf (59 off 56) helped their side to a healthy 233 all out from 39.3 overs before pace bowler Wahab Riaz and spinner Shahid Afridi ran thro' the clueless Bangla line-up with the probing spells to restrict the hosts to 163/8.
Skipper Mohammad Ashraful top-scored for Bangla with a turtle-esque 56*. Razzak (26), Tamim Iqbal (29) and Mushfiqur Rahim (15) were the only other Bangla batsmen to reach double figure mark.
Despite a bright start Bangla started losing wickets at regular intervals after opener Shahriar Nafees (9) was caught behind by Kamran Akmal off a delivery from debutant seamer Riaz.
Earlier Butt and Akmal provided Pakistan a blazing start putting on 75 for the opening wicket. Kamran Akmal, dominating new-ball bowlers Shahadat Hossain and Mashrafe Mortaza with attractive strokes.
Debutant seamer Dolar Mahmud provided the breakthrough in the 12th over when he had Akmal (25) caught by wicket-keeper Mushfiqur Rahim, who dived to his right to bring off a low catch.
Younus Khan was run out in the next over, but Butt and Yousuf bolstered the innings with a 65-run stand for the third wicket.
Butt struck 10 fours in his 84-ball knock and Yousuf seven boundaries in his 56-ball innings. It was Butt's eighth half-century and Yousuf's 62nd.
Misbah-ul-Haq then built on the efforts of Butt and Yousuf, smashing two sixes and three fours in a 22-ball 39.
Leg-spinner Alok Kapali dismissed Shahid Afridi (20) and Yousuf in the same over to finish with 3/49, his best in 56 one-day internationals.
Left-arm spinner Abdur Razzak finished with 3-35, including two wickets in the last over of the innings.
Pakistan face India in the second match of the series in Mirpur on Tuesday.