Hamilton Masakadza's 85 helped Zimbabwe earn their first one-day international victory over Pakistan since 1998.
Chasing a target of 245 in the opening game of the three-match series in Harare, opener Masakadza set Zimbabwe on the way to a seven-wicket success.
Zimbabwe skipper Brendan Taylor (43no) and Sean Williams (39no) steered their side over the winning line with 10 balls to spare after Saeed Ajmal had denied Masakadza a century.
Masakadza and Vusi Sibanda got the run chase off to a solid start with a 107-run partnership in 23.3 overs before Pakistan spinner Ajmal won an lbw verdict against Sibanda (54).
Ajmal (2-44) also accounted for Masakadza, caught in the covers to end a 104-ball effort that included nine fours and a six, and left-arm seamer Junaid Khan (1-55) removed Timycen Maruma (18) to leave Zimbabwe on 201-3 after 43 overs.
Williams joined Taylor in the middle and blasted 39 off 23 deliveries to ensure Zimbabwe got home in the penultimate over, finishing off proceedings with a six.
Pakistan skipper Misbah-ul-Haq finished on 83 not out in his side's total of 244-7 after opting to bat first.
All of the top four made contributions, openers Nasir Jamshed (27) and Ahmed Shehzad (24) ensuring a steady start with a 56-run stand.
Mohammad Hafeez and Misbah put on 99 for the third wicket with Hafeez's 71-ball 70 featuring six fours and three sixes.
Misbah batted through to the end of the innings, his 85-ball contribution contained three fours and two sixes, while Zimbabwe seamers Brian Vitori (2-42) and Tendai Chatara (2-32) each picked up two wickets.
The second match of the series takes place at the same venue on Thursday.