Hollenberg is a city in Washington County, Kansas, United States.

[5] According to the United States Census Bureau, the city has a total area of 0.08 square miles (0.21 km2), all land.

[6] The community is approximately 1.5 miles (2.4 km) south of the Kansas-Nebraska state line.

The 2020 United States census counted 10 people, 5 households, and 0 families in Hollenberg.

There were 15 housing units at an average density of 205.5 per square mile (79.3/km2).

100.0% of households consisted of individuals and 40.0% had someone living alone who was 65 years of age or older.

There were 23 housing units at an average density of 287.5 per square mile (111.0/km2).

50.0% of all households were made up of individuals, and 11.1% had someone living alone who was 65 years of age or older.

There were no families and 14.3% of the population living below the poverty line, including no under eighteens and 100.0% of those over 64.

The community and nearby rural areas are served by Barnes–Hanover–Linn USD 223 public school district.