
Cook, who had scored his career-best 137 in the series-opener at the same venue on Friday, slammed 102 to help England manage a competitive total of 250-4 after they opted to bat.
In reply, skipper Misbah-ul-Haq and Imran Farhat played the knocks of 47 runs apiece but the target remains beyond Pakistan’s range as they were skittled out for 230 in 49 overs.
Steven Finn, who had claimed four wickets in the series-opener, finished with the career-best figures of 4-34 to anchor his side’s victory.
Openers Mohammad Hafeez (26) and Imran Farhat (47) got off to Pakistan a slothful but strong start and took the total to 61 in 15 overs before former was caught at mid-wicket by Jonathan Trott off paceman James Anderson.
Farhat stitched up 31 more runs for the second wicket with Azhar Ali (31) before getting run out while feeling for a risky single.
This time off-spinner Samit Patel struck drastically and extended Pakistan’s woes by dismissing Ali and Younis Khan (5) in quick succession.
Shahid Afridi lulled Pakistan by slamming a quick-fire18 but his dismissal calm down the matters for England.
England then enjoyed a tumble of wickets as Pakistan lost the last four wickets for just 23 runs.
Earlier, leading from front Cook hit his fourth ton and became the first England skipper and ninth batsmen for his country to crack back-to-back hundreds in ODIs.
The 27-year-old southpaw developed 67-run opening stand with Kevin Pietersen (26) before adding 49 with Trott (23) for the second and 78 for the third wicket alongside Ravi Bopara (58).
Cook, whose 121-ball vigil was studded with 10 boundaries, eventually fell in 42nd over, spooning a return catch to leg-spinner Afridi.
The next two games are scheduled in Dubai on Saturday and Tuesday. One-day series will be followed by three Twenty20 internationals.
Pakistan VS England 2nd ODI Scorecard