After Tuesday's official announcement, Malcom is to undergo a medical and travel to the club's pre-season tour of North America on Wednesday.
"This is a boyhood dream come true" the forward told Barcelona official media.
"I hope to bring a lot of joy to the fans. I can't wait to get started. I'm here to help my teammates with my style.
"It is a unique feeling. I'm realising a dream and I'm going to play for the best club in the world.
"I always try to help my teammates and I am looking forward to meet the ones I will have at Barcelona. It is important to know the people you are going to play with."