The Royal Military College at Duntroon will undergo upgrades costing up to $75 million under plans to increase space for trainees at the facility.
Defence Department documents show the college will refurbish three residential buildings, and build new accommodation for staff cadets and training staff.
The college will also expand a block used for military instruction to create room for a new lecture theatre.
The Defence Department, which is looking for contractors to expand the facilities, says the project will help Duntroon meet demand until another major redevelopment scheduled for 2030.
It said the college has experienced significant infrastructure and facility shortfalls because of increased demand for training.
The construction project will cost between $65 million and $75 million, and is expected to finish in December 2026.
Documents on the government's contracts website, Austender, show the college will build a new three-level, 95-bed facility to help it accommodate 550 staff cadets, the peak number forecast until the next major redevelopment.
The expansion of its military instruction block will provide working accommodation for staff, and will include a new lecture theatre room to accommodate 250 people.
Budget papers last year revealed Defence was planning a separate, ambitious four-year project to fit out Canberra offices.
