The Police Federation of England and Wales said demand is outstripping police resources as the number of officers voluntarily resigning is at its highest across the two nations.
Home Office figures show 52 full-time police officers voluntarily left Gwent Police in the year to March. It is up from 48 the year before.
Including officers who retired or were fired, a total of 97 left the force last year.
It meant Gwent Police had a leavers rate of 6.8%, excluding transfers to other forces.
Across England and Wales, a record high 4,575 full-time officers voluntarily resigned from policing last year. It was a 33% increase from 3,433 in 2021-22.
Overall, the leavers rate also reached its highest level at 6.6%.
Steve Hartshorn, Police Federation of England and Wales national chair, said the 'worrying' figures echo the concerns thousands of officers have been raising.
He said: "Our members are doing their utmost to protect the public, but demand is continuing to outstrip resources.
"It is paramount the service not only recruits, but retains, which will only be possible if pay and conditions are improved, to give members of the public the service they deserve."
He added: "The focus going forward needs to be on pay restoration."
While the turnover rate was at its highest, it was met by a joiners rate of 11.1%.
It meant the headcount for all forces increased from 140,200 officers in March 2022 to 147,400 in March of this year.
Mr Hartshorn added it is only a slight increase from 2010’s headcount of 143,700 while the UK population has grown ‘rapidly’ and the nature of crime ‘continues to increase in complexity’.
In Gwent Police, the force grew from 1,430 officers in 2022 to 1,526 in 2023.
A Home Office spokeswoman said: "We have delivered a record number of police officers across England and Wales. We made it very clear to police forces that this large investment means we expect officer numbers to be maintained and they should have robust plans in place to ensure this.
"Policing is a career like no other and our latest survey of new recruits showed 82% respondents were satisfied with the job and 77% plan to stay in policing for the rest of their careers."