"The UEFA executive committee has decided to give its unanimous support to Mr Joseph S Blatter in the upcoming FIFA presidential elections and strongly recommends all UEFA member associations to do likewise," UEFA said in a statement on Friday.
The statement was signed by the 16 members of the executive committee of European football's ruling body.
Blatter will be up against Asian Football Confederation president Mohamed Bin Hammam of Qatar in the June 1 election and UEFA's announcement could potentially swing the vote in his favour.
Earlier this week, Blatter told the CONCACAF Congress in Miami: "I was not going to campaign here because at the beginning of congress the president of CONCACAF said: 'You don't need to campaign in this region'."
"The Americas in South America or CONCACAF have always been my base and I don't think that anything has changed especially after this congress and the declarations made at this congress."
Blatter, the eighth head of FIFA since world football's ruling body was founded in 1904, joined as a technical officer in 1975 and was general secretary from 1981-98 under the presidency of Joao Havelange.
Four years later Blatter claimed a landslide 139-56 victory over Cameroon's Issa Hayatou and, if anything, his grip on FIFA has tightened since then.
