Phil Sharpe joined the practice as an advisory director in 2014 and has more than 20 years' experience in corporate finance.
As a partner he will head Grant Thornton's 30-strong advisory team and will work to further invest in its growth.
"Cambridge is a vibrant city which is home to many dynamic, growth focused businesses and is expected to grow significantly in scale over the coming years," Sharpe said.
"This strong market presents an exciting opportunity for our team and although we’re already at the forefront of the advisory market, we feel there is more to go for.
"We have recently invested in our growing team and will continue to seek out the very best, talented individuals to further enhance our capabilities and market penetration."
Practice leader at Grant Thornton’s Cambridge office, Darren Bear, added: "As a valued member of our expanding team, we would like to congratulate Phil on his promotion. Phil has consistently demonstrated his considerable expertise and commitment to the firm and we have no doubt his abilities will continue to benefit other businesses, as well as our own, across the region."