The 19-year-old is seen as the long-term replacement for Antoine Semenyo who joined Manchester City earlier this month in a £65M deal which leaves the Cherries lacking in attack.
Rayan is reportedly keen to come to the Premier League and the clubs have been in talks over a possible move over the past few weeks.
Transfer guru Ben Jacobs provided an update on the situation on Wednesday afternoon, confirming the deal is set to go ahead.
“Rayan has agreed a 5.5-year contract at Bournemouth.
“He will travel to formalise the move on Friday.✈️
As first reported by journalist Eduardo Burgos who stated:
“Bournemouth closes the signing of Rayan.
“Vasco da Gama will receive 35M€ in fixed and variable payments for the player, plus retaining a % of future sale.
“The player travels to England at the end of the week. Contract for 5.5 seasons, until 2031.”
Rayan has scored 25 goals in 99 games for Vasco da Gama and has only played one game this season due to constant talks about his future which have included links to Premier League rivals Newcastle United.
Bournemouth signed Hungary midfielder Alex Toth for £10.4m from Ferencvaros on Tuesday and will continue to splash the cash on Rayan who could follow in the footsteps of Philippe Coutinho who was produced by the Vasco academy.