The 20-year-old joined Palmeiras on loan from Coritiba last month.
Keirrison told Terra: “Ever since I was young, I have identified with the country and the club.”
He continued: “I do not have anything against the other clubs, but I like Barcelona, because I saw a lot of Romario and Ronaldo when I was young, so it is a very large dream to play for Barca.
“Another dream is to play with a great player like Messi.”
Keirrison have previously been linked with Real Madrid, Atletico Madrid, Valencia, Manchester United and Liverpool.