Prime Minister Tony Abbott has urged Australians to reaffirm their pledge to make their country a beacon of hope in uncertain times.

In his annual Australia Day message, Mr Abbott also said work towards constitutional recognition of indigenous Australians would continue.

Australia Day was about honouring the traditional owners of the land and paying tribute to those who enshrined freedom, fairness and unity in the constitution, he said.

It was also about reaffirming a pledge to make the country a beacon of hope and optimism in an uncertain world.

"To be an Australian is to have won the lottery of life," Mr Abbott said.

"But we can't rest on our laurels and everyone has a part to play in sustaining a country that is strong and prosperous, free and fair."

Mr Abbott said 2015 would be significant in commemorating the centenary of the Gallipoli campaign, and perseverance towards constitutional recognition.

"This spirit of generous inclusion has always marked our nation at its best," he said.

© AAP 2015