ADF personnel are deployed to Iraq, Afghanistan, the broader Middle East region and South Sudan, as well as in Australia's northern waters.
Chief of Joint Operations Vice Admiral David Johnston said the ADF would continue serving on operations over a time more often reserved for holidays and festive celebrations.
"Christmas is a time to reflect on the sacrifices made by the men and women of the ADF, as well as their family and friends back home who support them," VADM Johnston said.
"I remain incredibly proud of the professionalism and contribution made by all Defence personnel who supported operations throughout the year.
"Thank you to those who deployed this year and their loved ones at home who support you. To those away this Christmas, take time to celebrate with your ADF colleagues and our coalition partners."
The number of defence personnel deployed overseas during Christmas this year has fallen compared to last year, which saw around 2,300 ADF personnel deployed during the festive season.