Sebastian James will stay with the group until November, when he will leave to take on another job in the healthcare sector.
The tech stock ended June trading with a 2024 gain of 188%, while the pharmacy chain has fallen 54%.
Sebastian James, who has run Boots since 2018, will remain in the post until November before taking up a new role elsewhere, the person told Reuters. Walgreens did not respond to Reuters' request for comment outside business hours. Sky News first reported James' exit, saying he had taken a role in the healthcare industry.