Lucius Roy Holbrook was a major general who commanded the United States Army's Philippine Department from 1936 to 1938.

The Philippine Department was a regular United States Army organization whose mission was to defend the Philippine Islands and train the Philippine Army. On 9 April 1942, during World War II, the organization surrendered to the Japanese. The department and its sub-units were predominantly under the command of American officers, including an American general, while the majority of the troops were enlisted Filipinos, known as the Philippine Scouts (PS). The primary force of this department was the Philippine Division. Of the 22,532 troops, 10,473 were members of the Philippine Division itself.