Garza County is a county located in the U.S. state of Texas. As of the 2020 census, its population was 5,816, of which most of the population were residing in its county seat, and only incorporated municipality, Post. The county was created in 1876 and later organized in 1907. Garza is named for a pioneer Bexar County family, as it was once a part of that county.

Charles William Post was an American innovator, breakfast cereal and foods manufacturer and a pioneer in the prepared-food industry. He was the founder of what is now Post Consumer Brands.