Mary opted for a simple floor length black gown which she accesorised with a black blazer that had gold shoulder details reminiscent of military clothing.
The military inspired jacket was a touching way to honour the navy officers at the event.
Mary turned heads in her military inspired ensemble.
Keld Navntoft / Ritzau Scanpix
Mary also adorned the jacket with a number of royal orders and wore her hair slicked back in a low bun. She also carried a small black clutch to the event.
Prince Frederik looked dashing in the Danish Navy uniform which he also adorned with royal orders.
The Queen hosts the annually honorary banquet for the Army, the Navy, and the Air Force.
Mary and Frederick were all smiles at the event.
Keld Navntoft / Ritzau Scanpix
The honorary banquet is held alternately between the three units, and this year the Navy officers of Admiral and Commander's Degree received the Honorary Sign for good service at the Navy
Princess Mary will be out again tomorrow to attend a meeting with the Parliamentary Intergroup for Sustainable Development Goals.