The DR Congo international has received his work permit from the Football Association, meaning he can now join up with his new teammates on Tyneside.
The 20-year-old agreed personal terms and passed his medical last week but must now leave the country to apply for his work visa, with Newcastle expecting him back in the North East by the middle of next week.
“This is the biggest league in the world and I’m very proud to wear the shirt for this team and play in this league,” said Mbemba.
“I’m going to do everything I can to help make the supporters happy, to help out my teammates and to bring something extra to the team.
“I know the team very well. I’ve watched the Premier League and I know this is a massive team with big players and with a great coach. I’ve come here to Newcastle United because it’s a very good move in my career to play for such a famous club. I am excited for the season ahead.”
Head coach Steve McClaren said: “We are delighted that Chancel is now a Newcastle United player after it took a little longer than we had hoped.
“He is a proven performer at the highest level, he’s powerful, combative and will add quality to our defence. He also has an eye for goal which is an extra asset for us.
“We will get him integrated into the squad quickly once he is with us. Unfortunately, due to the time it takes to process the visa application that won’t be in time for our final friendly on Saturday, but our focus will be to make sure he will be ready and available as soon as possible.
“I’m sure our supporters will take to him very quickly. He’s the sort of player fans will enjoy watching.”
Mbemba becomes McClaren’s third signing of the summer following the arrival of his former Anderlecht teammate Aleksandar Mitrovic and Georginio Wijnaldum, who joins from PSV Eindhoven.