By Eoin Blackwell, AAP Papua New Guinea Correspondent
PNG's parliament on Tuesday also passed laws allowing for five types of execution - hanging, lethal injection, medical death by deprivation of oxygen, firing squad and electrocution.
The parliament also repealed the controversial 1971 Sorcery Act, meaning those convicted of killing accused "sorcerers" will be sentenced to death, Prime Minister Peter O'Neill's spokesman, Daniel Korimbao, said in a statement.
"These are very tough penalties, but they reflect the seriousness of the nature of the crimes and the demand by the community for parliament to act," he said.
"Which method (of execution is) to be used will be determined by the head of state on advice from the National Executive Council (cabinet)."
Death by hanging has been part of PNG's criminal code since before independence from Australia in 1975, but has not been enforced since 1954.
Under the new amendments, the death penalty will be enforced for crimes such as aggravated rape, pack rape, or where the victim is a child under 10 years of age.
Kidnapping will carry a prison term of 50 years without remission or parole, while kidnapping for ransom carries life imprisonment without parole.
Theft of money between 5 million kina ($A2.4 million) and 9.99 kina million will attract 50 years without parole.
Theft of money or property worth 10 million kina or more will be punished with life imprisonment.
A series of violent murders and sex crimes this year prompted the PNG government to enact the measures in an attempt to deter crime.
In particular, women accused of being witches have been killed in increasingly gruesome public show-trials.
In one incident, a young mother, Kepari Leniata, was stripped and burned alive in a public market, while in another, a former teacher, Helen Rumbali, was beheaded.
Some killings have been carried while police were present, with officers powerless to intervene against large crowds of armed attackers.
UN Women, a division of the United Nations, has welcomed the repeal of the Sorcery Act, but declined to comment on the use of the death penalty.
"UN Women congratulates government on repealing the Sorcery Act and looks forward to new initiatives that will counter the rising violence against women and men, and bring an end to extra-judicial killings," an agency spokesperson said.
Church groups and civil libertarians have objected to the measures and pointed out police have trouble enforcing current laws.
"We have got current systems and structures in place that are not working, we can't even prosecute a shoplifter, and here we are trying to impose the death penalty," women's rights campaigner Esther Igo recently told Radio Australia.
"We believe that we should get our structures, the current enforcement system, working before we can look at an extreme penalty."
Mr Korimbao told AAP tougher drug penalties, alcohol licensing rules and stricter penalties for home brew have been temporarily deferred.
"They are still being worked on," he said.
Two weeks ago, Mr O'Neill apologised to women in PNG for the high levels of sexual and domestic violence they experienced and pledged to pass the stricter penalties - penalties he described as "draconian."