|Motto: "History, Hospitality, Opportunity"|
|• Total||0.4 sq mi (1.1 km2)|
|• Land||0.4 sq mi (1.1 km2)|
|• Water||0.0 sq mi (0.0 km2)|
|Elevation||833 ft (254 m)|
|• Density||1,934/sq mi (746.6/km2)|
|Time zone||Eastern (EST) (UTC-5)|
|• Summer (DST)||EDT (UTC-4)|
|GNIS feature ID||0498363|
Millersburg is located in northeastern Bourbon County at  reaching to the Nicholas County border. U.S. Route 68 (Main Street) passes through the center of town, leading southwest 9 miles (14 km) to Paris, the county seat, and 29 miles (47 km) to Lexington. It is 37 miles (60 km) northeast to Maysville on the Ohio River.,
As of the census of 2000, there were 842 people, 356 households, and 248 families residing in the city. The population density was 2,432.5 people per square mile (928.9/km²). There were 390 housing units at an average density of 1,126.7 per square mile (430.2/km²). The racial makeup of the city was 94.66% White, 3.44% African American, 0.83% Native American, 0.59% from other races, and 0.48% from two or more races. Hispanic or Latino of any race were 1.19% of the population.
There were 356 households out of which 29.5% had children under the age of 18 living with them, 50.8% were married couples living together, 14.6% had a female householder with no husband present, and 30.3% were non-families. 26.7% of all households were made up of individuals and 11.8% had someone living alone who was 65 years of age or older. The average household size was 2.37 and the average family size was 2.84.
In the city the population was spread out with 24.0% under the age of 18, 8.4% from 18 to 24, 27.0% from 25 to 44, 24.9% from 45 to 64, and 15.7% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 91.8 males. For every 100 females age 18 and over, there were 92.8 males.
The median income for a household in the city was $25,500, and the median income for a family was $32,692. Males had a median income of $29,861 versus $18,333 for females. The per capita income for the city was $13,906. About 12.4% of families and 15.7% of the population were below the poverty line, including 23.0% of those under age 18 and 11.6% of those age 65 or over.
- Blanton Collier, American football coach born in Millersburg
- Jim Kelly, martial artist of the 1970s, born in Millersburg. He co-starred with Bruce Lee in the film Enter the Dragon.
- Mae Street Kidd (1909–1999), State Representative 1968-1984, representing Louisville's 41st state legislative district; born in Millersburg
- Alma Bridwell White, founder of the Pillar of Fire Church and Ku Klux Klan advocate
Millersburg is the site of the headquarters of the U.S. Army Cadet Corps, the National Cadet Training Center, and the Forest Hill Military Academy, all on the historic campus of the defunct Millersburg Military Institute (MMI).
The U.S. Army Cadet Corps – the largest entity within Millersburg – provides two to six weeks of career exploration programs during the summer. All cadets must be crime-free, drug-free, and doing well in school. Since 2009, USAC has hosted over 1,000 young people from throughout the United States and from 21 foreign countries. Graduation ceremonies are held throughout the summer. Each ceremony is open to the public.
Forest Hill Military Academy, a preparatory school for young men and women in 6th through 12th grades, was scheduled to open in August 2012.
- "Geographic Identifiers: 2010 Demographic Profile Data (G001): Millersburg city, Kentucky". U.S. Census Bureau, American Factfinder. Retrieved November 21, 2013.
- "US Gazetteer files: 2010, 2000, and 1990". United States Census Bureau. 2011-02-12. Retrieved 2011-04-23.
- "American FactFinder". United States Census Bureau. Retrieved 2008-01-31.