Australia has a deal with the US to take refugees from Australia's offshore facilities but there is no guarantee how many it will accept, ABC News reported.
Dutton said the former Labor government struck a deal for PNG to resettle people and he expected the country to fulfil the commitment.
"We'll work with the PNG Government but some people will remain in PNG," he told Sky News.
"We've been very clear with the PNG Government: that's the nature of the agreement struck between Prime Ministers [Peter] O'Neill and [Kevin] Rudd.
"PNG itself is a signatory to the [refugee] convention and to the protocols, PNG has the responsibility to settle those people.
Dutton said about 36 people had already been settled in the country.
Dutton also said he expected the Manus Island detention centre to close before the end of October after a court decision last year.
Dutton said US Homeland Security and State Department officials were examining the cases of people on Manus and sounded hopeful many would be accepted.
"We've been very encouraged by the approach of the officials. We think there's significant scope for a large number of people but we don't have an exact number as yet," Dutton said.