They are MPs Andrew Laming and Cathy McGowan and senators Claire Moore and Linda Reynolds, who will observe the voting along with staff from the Australian High Commission in Port Moresby.
"Australia is working closely with PNG to support the election, including by providing experts from the Australian Electoral Commission, the Australian Civilian Corps and the International Foundation for Electoral Systems," said Foreign Minister Julie Bishop.
"Our assistance also includes voter awareness initiatives, support for female candidates and election-related training for journalists."
Bishop went on to say that the Australian Defence Force had provided logistics support to the PNG Electoral Commission, including helicopters and planes to help transport election material to regional centres before the polling period.
"This assistance will help to strengthen electoral processes, and deliver polling operations in a country with some of the world's most difficult terrain," Bishop said.
"As our nearest neighbour, Australia has a shared interest in PNG's security and economic development. Our relationship is built on rich ties between our peoples which have evolved into deep business and economic links - nearly 5000 Australian companies do business with Papua New Guinea and our investments in PNG are valued at around $18.4 billion," she said.