Stanberry is a city in Gentry County, Missouri, United States. The population was 1,129 at the 2020 census. Stanberry was platted in 1…Stanberry is a city in Gentry County, Missouri, United States. The population was 1,129 at the 2020 census. Stanberry was platted in 1879 when the railroad was extended to that point. The community was named for J. J. Stanberry, original owner of the town site. A post office called Stanberry has been in operation since 1879.