Armstrong is a city in Howard County, Missouri, United States.

[7] According to the United States Census Bureau, the city has a total area of 0.82 square miles (2.12 km2), all land.

24.3% of all households were made up of individuals, and 12.6% had someone living alone who was 65 years of age or older.

The racial makeup of the city was 92.33% White, 5.92% African American, and 1.74% from two or more races.

30.4% of all households were made up of individuals, and 13.9% had someone living alone who was 65 years of age or older.

About 9.0% of families and 16.5% of the population were below the poverty line, including 30.6% of those under the age of eighteen and 10.8% of those 65 or over.