Brigadier General Thomas Griffiths, CMG, CBE, DSO (29 September 1865 – 16 November 1947) was a Welsh-born officer in the Australian Army who served in mainly administrative positions during the First World War.

After the Federation of Australia, he became a clerk in the Australian Military Forces, serving at the Adjutant General's office at Army Headquarters in Melbourne.

In September 1908 he was appointed secretary to the Military Board with the honorary rank of lieutenant in the Administrative and Instructional Staff.

As such he was deputy to Lieutenant Colonel Cecil Foott, who was responsible for all administration and logistics in the 1st Division area at Anzac Cove.

[1] In October 1915, Griffiths was transferred to the staff of the Australian and New Zealand Army Corps, then under the command of Lieutenant General Sir William Birdwood.

For his work at Gallipoli and in the subsequent reorganisation of the AIF in Egypt, Griffiths was mentioned in despatches and awarded the Distinguished Service Order (DSO).

In May 1916, with Birdwood now commanding I Anzac Corps which was intended for service on the Western Front, Griffiths was promoted to lieutenant colonel and formally became Assistant Adjutant General of the AIF.

The armistice rendered his task moot, and he returned to London in December and resumed duty at AIF Headquarters for several months.

He was highly thought of by his superior, Brigadier General Brudenell White[1] and Charles Bean wrote that he "was one of the great figures of the Australian Army.