The US fast food giant said the relationship was agreed, but Easterbrook had “violated company policy” and “bad judgment”.
In an email to the staff, the British businessman acknowledged the relationship and said it was a mistake.
“Given the values of the company, I agree with the board that it’s time for me to move on,” he said.
Mr. Easterbrook, 52, divorced, first worked for McDonald’s in 1993 as a director in London before moving up the corporate ladder.
He left in 2011 to become the boss of Pizza Express, then of the Asian food chain Wagamama, before returning to McDonald’s in 2013, finally becoming his boss in the United Kingdom and Northern Europe.
Easterbrook is widely known for revitalizing the company’s menus and restaurants, reshaping stores and using better ingredients.
The value of his shares has more than doubled during his tenure in the United States.
Under his leadership, McDonald’s has also expanded its delivery and mobile payment options to focus on convenience.
The board of directors of the fast food giant voted to leave Easterbrook, born in Watford, on Friday, after an exam.
He also stepped down as president and board member of McDonald’s.
The company rules for managers forbid them to engage romantically with a subordinate.
She will release Monday the details of Mr. Easterbrook’s severance pay, which will be followed closely.
The company has been criticized for the amount it pays to its executives, and Mr. Easterbrook has been scrutinized for his pay of US $ 15.9 million (9,347,849,966 FCFA) in 2018. .
This is 2,124 times the median salary of the employees, ie 7,473 US dollars (4,393,263 FCFA).
He will be replaced by Chris Kempczinski, most recently President of McDonald’s USA, with immediate effect.
In a statement, Mr. Kempczinski thanked Mr. Easterbrook for his contributions, adding, “Steve brought me to McDonald’s and he was a patient and helpful mentor.”
Last year, Intel boss Brian Krzanich resigned for having a relationship with an Intel employee, which was against the company’s rules.