Bateman is set to retire in November after 36 years at the youth work charity which develops non-formal education programmes across the UK.
Before joining UK Youth as the charity's communications and advocacy manager last year, Hill worked for the NSPCC.
On her appointment, she said: "I am passionately committed to continuing the excellent work John has undertaken in recent years.
"The charity has never been in a stronger position, rolling out so many exciting programmes for young people such as the Think Big programme with O2 or our Youth Achievement Foundations.
"We have a big responsibility to support young people, who need organisations such as UK Youth more than ever before. I am looking forward to working with our members, sponsors and supporters in the public, private and voluntary sectors to make a real difference for young people."
