Alexander Hammett Marks, CBE, DSO (6 August 1880 – 18 January 1954) was an Australian physician and military officer.

He was the first[1] son of Dr Charles Ferdinand Marks, a surgeon and later member of the Queensland Legislative Council, and his wife Elizabeth (née Stodart).

With the outbreak of war, Marks enlisted in the Australian Imperial Force and was posted to the 3rd Field Artillery Brigade as a regimental medical officer.

In October, he was sent back to France where he commanded the 1st Australian Casualty Clearing Station, serving in this capacity until September of the following year when he was promoted to the rank of colonel and assistant director of Medical Services to the 1st Division.

He was the President of the Medical Defence Society of Queensland from 1931 to 1946, and held a number of positions including "honorary radiologist" and "senior gynaecologist" at the Brisbane General Hospital.