Men aged in their 30s who have been involuntarily medically discharged from the Defence Force are four times as likely to die by suicide than Australian men of the same age.
That is one of hundreds of findings released in a report by the Australian Institute of Health and Welfare on Friday afternoon, which also found men who have serve for less than a year are at a significantly higher risk of suicide.
Men who were involuntarily discharged were 2.4 times at risk compared to those who were voluntarily discharged.
The report is the most recent in a series of three made public over the last few years investigating the period between 2001 and 2015.
"For men discharged involuntarily for medical reasons, suicide rates were significantly higher in all age groups examined, compared with rates for all Australian men of the same age," the report said.
"71 per cent of suicide deaths of ex-serving personnel occurred in men discharged from the ADF for less than 6 years at the time of death."
The institute also found men who served for less than one year between the ages of 18-29 had a suicide rate of 2.3 times that of the general population in the same age group.
Men at all ranks other than commissioned officers were 2.8 times more likely to die by suicide than those who were officers.
This was amplified in younger age groups - 18-29 year olds that were not commissioned officers had a suicide rate of 1.7 times of men the same age.
Former members of the Navy had a 2 per cent higher risk of suicide compared to the Army and Airforce, but the institute said there was not any statistically significant difference between the three arms of the defence force.
