Belton who will replace Robert Overend on EY’s board on 1 July, will also take on the role as professional practice director and UK audit compliance principal for EY.
She is currently an assurance partner within EY's professional practice group, having been with the firm for more than 27 years.
After joining the firm in 1991, she was made partner in 2002, and has experience within the oil and gas sector as audit engagement partner across a range of companies.
Belton is a chartered accountant and sits on the audit and assurance faculty committee and the practice committee at ICAEW.
Meanwhile, Tonia Lovell has been appointed as an independent non-executive (INE) to replace Rosemary Martin following her retirement last year.
Although the appointment is not a board appointment Lovell will attend board meetings alongside her two fellow INEs David Thorburn and Sir Peter Westmacott.
Previously, Lovell was general counsel for corporate governance at Unilever, having spent 21 years with the consumer goods company.
EY UK chairman, Steve Varley, said that these appointments come “at a significant time for the profession”.
He added that he was confident both Lovell and Belton would "bring the challenge and insight needed to further strengthen our UK leadership, governance and how we run our business”.