Claire Forbes joins the YJB in June from the Advertising Standards Authority, where she is director of comms and marketing.
She replaces Sean Larkins, who moves to Chime Communications' polling arm Opinion Leader Research.
Forbes will be responsible for a 15-strong comms team and will report to YJB chief executive Ellie Roy.
The YJB works to prevent young people from offending and reoffending. Forbes' appointment comes as the Government's ten-year record on youth justice came under attack in a report by the Centre for Crime and Justice Studies at King's College London, which argued that a massive increase in spending has had almost no impact on youth crime.
The report claims that ministers have overstated the success of the Government's reforms, and that most youth justice targets had been missed.
A spokesman for YJB said one of the main challenges Forbes would face is 'increasing public confidence in the youth justice system'.
'The priority for the YJB must be to have effective, collaborative and trusted relationships with those upon whom the organisation is reliant,' the spokesman said.