The report documents "systematic and widespread human rights violations and abuses," a spokesperson said in Geneva on Tuesday.
High Commissioner for Human Rights Michelle Bachelet called on the international community to "stem the spiral of violence" in the country.
According to the report, the military is actively targeting the civilian population, bombing residential areas and shooting, burning, arresting and torturing people arbitrarily.
Reports suggest that people have been: suspended from the ceiling without food or water; forced to stand upright for hours in solitary confinement; tortured with electrical shocks; and forced to take drugs.
Muslim prisoners have allegedly been forced to eat pork, in violation of their religious principles.
The report also cites an event in the region of Sagaing in the northwest of Myanmar in which more than 40 people were ambushed and killed by soldiers.
Some bodies had their hands and feet tied.
In the Kayah region in the east of the country, soldiers are said to have burned the bodies of 40 men, women and children, some of whom were alive when set ablaze.
At least 1600 people have been killed by security forces and their associated groups, with more than 12,500 arrested, the report states.Â
According to the UN, at least a further 543 people have also been killed for alleged support of the military.
The commission estimates that 440,000 people have been displaced and 14 million are in need of humanitarian assistance.
Democratically elected Aung San Suu Kyi, a Nobel Peace Prize recipient, remains incarcerated.
