Approximately half (49%) of managers have never received training on mental health in the workplace, according to research by the Chartered Management Institute (CMI).
Its survey of 940 UK managers also found that only 30% have received this training in the last year, while a further 20% did so more than a year ago.
Ann Francke (pictured), chief executive officer at CMI, said: "Given the vital importance of maintaining mental health at work, the fact that half of managers have never been trained in this area shows we have a very long way to go to make this a part of essential workplace practice."
Around half (51%) of managers have had a member of staff disclose a mental health problem to them; this means that 62% of respondents who have spoken with an employee about mental health issues have either never had any relevant training or received their training over 12 months ago.
Senior managers are less likely than their junior counterparts to receive training on managing mental health at work, with 51% of senior respondents never having this training, versus 44% of junior managers.
More than half (52%) of managers over the age of 50 have not had training, compared to 42% of respondents aged between 18 and 29, while 52% of male managers have also not been trained in this area. In comparison, 42% of female managers have not been trained in helping employees with their mental health.
Francke added: "CMI research shows that mental health at work is an issue that cannot continue to be ignored, as over 50% of managers have had a mental health problem disclosed to them by colleagues.
"Line managers play a absolutely critical role in supporting employees' mental health and wellbeing. Employers are already required by law to provide training on physical health and safety. It's time the same requirements applied to mental health."