Romero has been a reliable performer for United since arriving in July 2015.
Last season he made 28 appearances for the club and started the Europa League final victory over AFC Ajax ahead of regular number one David de Gea.
And he has now been rewarded with a new contract extending his deal until June 2021, with the option to extend for a further year.
Romero said: “I am delighted to have signed a new contract. Who wouldn’t want to be at the biggest club in the world?
Manchester United stars snapped out clubbing after LA Galaxy win Sun, July 16, 2017
Manchester United stars were snapped attending an exclusive Adidas event after their pre-season win over LA Galaxy
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Rashford, Tuanzebe, Mkhitaryan and Darmian with model Emily Ratajkowski
Sergio Romero has signed a new contract
"We have great goalkeepers here and we are always learning from each other. Of course, it was a very proud moment for me and my family to be part of the Europa League final, and I am looking forward to helping the team build on last season’s success in 2017/18.”
United boss Jose Mourinho added: “Sergio is a great goalkeeper and professional.
"He had a good season and outstanding performances, especially in our Europa League success.
"Sergio deserves his contract, and for Manchester United to have Sergio and David is amazing in such an important role.”
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