The Texas State Guard (TXSG) is part of the state military force of Texas, and one of three branches of the Texas Military Forces. Along with the other two branches, the TXSG falls under the command of the Governor of Texas and is administered by the Adjutant General of Texas, an appointee of the Governor. The other two branches of the Texas Military Forces are the Texas Army National Guard and the Texas Air National Guard.

The Adjutant General of Texas is the commander and chief executive officer of the Texas Military Department, the executive department of the Texas Military Forces. The adjutant general's position of authority over Texas Military Forces is second only to the commander-in-chief, the governor of Texas. This position is analogous to the United States secretary of defense. The adjutant general of Texas is appointed by the governor of Texas with the advice and consent of the Texas Senate from Texas Government Code Title 4, Subtitle C, Chapter 437.003.