Marcus Daniel Cronin (9 January 1865 – 12 August 1936) was a United States military officer.

[1][2] On 12 January 1887, Cronin was commissioned as a second lieutenant of the infantry and served on the United States frontier from 1887 to 1893.

In the subsequent Philippine–American War, Cronin served as colonel of the United States Volunteers and later became assistant chief of the Philippine Constabulary from 1915 to 1917.

Following the United States' entry into World War I, Cronin was promoted to brigadier general of the National Army on 5 August 1917.

He became commander of the 163rd Infantry Brigade at Camp Gordon, serving in France as part of the American Expeditionary Force.