Personnel of the Australian Defence Force can be proud of their service, Prime Minster Scott Morrison has said.

In his Christmas message to the ADF, Mr Morrison said this year had been a particularly challenging one at home with bushfires and the COVID-19 pandemic.

“During the black summer of fires, we called on you to help keep Australians safe,” he said.

"We called on you again in response to a once-in-a-century pandemic, an unexpected challenge, but where once again the skill, adaptability and professionalism of our ADF was put to work."

While thousands of ADF personnel were deployed throughout Australia during the year, Mr Morrison also praised the nearly 1500 personnel currently serving overseas.

"We know you're far from home. You're upholding our nation's interests. You're defending our values. You are shining lights of our country," he said.

“Your service embodies not only who we are, but who we can be.”