Australian CEOs say they feel they do not really understand the needs of millennials, but that they want to hire and engage with more of this younger demographic over the next three years.

That's a key finding of KPMG's Global CEO Outlook of nearly 1300 CEOs from companies with annual revenues of $US0.5 billion to more than $US10 billion.

The survey, taken over March and April before Britain's historic decision to leave the European Union, included 53 Australian CEOs.

The majority of CEOs surveyed across the globe were public (70 per cent), and most were male (90 per cent).