Addyston is a village in Miami Township, Hamilton County, Ohio, United States, along the Ohio River. The population was 938 at the 2010 census.
The village was named after Matthew Addy, the proprietor of a local factory.
Addyston is located at 39°8′18″N 84°42′48″W (39.138292, -84.713204).
According to the United States Census Bureau, the village has a total area of 0.91 square miles (2.36 km2), of which 0.85 square miles (2.20 km2) is land and 0.06 square miles (0.16 km2) is water.
As of the census of 2010, there were 938 people, 372 households, and 228 families living in the village. The population density was 1,103.5 inhabitants per square mile (426.1/km2). There were 448 housing units at an average density of 527.1 per square mile (203.5/km2). The racial makeup of the village was 89.7% White, 5.7% African American, 0.2% Native American, 0.2% Asian, 0.1% from other races, and 4.2% from two or more races. Hispanic or Latino of any race were 1.9% of the population.
There were 372 households of which 33.6% had children under the age of 18 living with them, 33.6% were married couples living together, 20.7% had a female householder with no husband present, 7.0% had a male householder with no wife present, and 38.7% were non-families. 29.6% of all households were made up of individuals and 10% had someone living alone who was 65 years of age or older. The average household size was 2.52 and the average family size was 3.15.
The median age in the village was 34.2 years.