A report issued by the Australian Institute of Criminology says the Northern Territory has the highest rates of Indigenous deaths in custody in the nation.
The report documents overall deaths in custody across Australia to June 30, 2011.
Nationally, the number of deaths in custody, including police, prison or other forms of detention, was 80 in 2008-09.
In 2009-10, the number was 86, and in 2010-11, it was 85.
Across Australia, the number of deaths in prison custody rose from 43 in 2008-09 to 58 in both 2009-10 and 2010-11.
In 2010-11, six people died in custody in the Territory, five of them Indigenous.
The average age of those who died was 33.
Based on current statistics, the Territory has the highest rate of Indigenous deaths in custody in Australia.
Between 1979 and 2011, there were 32 deaths in custody in the Territory, 24 of which were Indigenous people.
The Territory has the highest incarceration rate of Indigenous people in Australia, with 97 per cent of juvenile detainees being Aboriginal.
Of adults in prison or other forms of detention, 82 per cent are Indigenous.
The Northern Australian Aboriginal Justice Association (NAAJA) says the high rates of Aboriginal incarceration and deaths in custody are a national disgrace.
Spokesman Jonathon Hunyor says governments are still struggling to address problems that were first highlighted 20 years ago.
"If we want to reduce Aboriginal deaths in custody, we need to reduce the number of Aboriginal people we are locking up," he said.
"Unfortunately, in the Northern Territory we are going in absolutely the opposite direction."