Marussia have yet to win a point this season. There are six races left in the season, starting at Yeongam on Sunday.
"It's amazing for me and I'm very happy to stay. I feel very confident with them," said Bianchi.
"I will have much more experience in Formula One (after his first season) and winter testing, and the new rules -- with new engines -- so it will be great for the team.
"I don't know what to expect but for sure it will be an improvement."
Bianchi's current team-mate is the fellow rookie Max Chilton.