He was provisionally suspended in September after a drugs test found elevated levels of testosterone in the former Manchester United player's system.
France international Pogba, 30, was randomly tested after Juventus' first match of the season on 20 August.
He was handed the ban by Italy's national anti-doping tribunal (Nado).
The failed drugs test was confirmed by Nado in a second sample in October, and the anti-doping prosecutor's office had requested the maximum four-year suspension.
More to follow.
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