According to the United States Census Bureau, the city has a total area of 6.4 square miles (16.5 km²), of which, 6.3 square miles (16.4 km²) of it is land and 0.04 square miles (0.1 km²) of it (0.31%) is water.
The community is at the junction of U.S. Route 45 (Church Street) and State Highway 32 (Monroe Avenue).
Due to the destruction brought to the area by the Civil War, few structures from this early period remain. However, the Elliot Donaldson House, constructed in 1850 and added to the National Register in 1980, as well as a handful of other homes, has survived.
In the mid nineteenth century, Okolona and the surrounding Black Prairie sometimes called the Black Belt or Prairie Belt, became what has been called the "Bread Basket of the Confederacy." The area was part of the original Cotton Belt of Mississippi well before the more famous Delta region gained fame and notoriety for major cotton production.
The Mobile and Ohio Railroad completed its tracks though Okolona in 1859 making the town a center for the ginning of cotton and its shipment to markets. The town grew along Main Street as a result of the railroad; however, virtually all commercial buildings from this period, including the depot were burned during the Civil War.
Five skirmishes or battles between Union and Confederate forces occurred in and around Okolona, the most famous of which occurred in February, 1864. In a running cavalry clash between Confederate General Nathan Bedford Forrest and Union General Sooy Smith, the Federals were defeated just north and west of town. General Forrest's brother, Jeffery, was killed in the engagement. The Battle of Okolona was fought nearby in 1864.
There are 1,177 households out of which 33.8% have children under the age of 18 living with them, 35.6% are married couples living together, 28.1% have a female householder with no husband present, and 33.2% are non-families. 30.2% of all households are made up of individuals and 14.8% have someone living alone who is 65 years of age or older. The average household size is 2.54 and the average family size is 3.16.
In the city the population is spread out with 30.0% under the age of 18, 8.9% from 18 to 24, 24.7% from 25 to 44, 22.0% from 45 to 64, and 14.5% who are 65 years of age or older. The median age is 34 years. For every 100 females there are 77.2 males. For every 100 females age 18 and over, there are 71.6 males.
The median income for a household in the city is $20,000, and the median income for a family is $32,147. Males have a median income of $26,217 versus $17,276 for females. The per capita income for the city is $11,486. 35.4% of the population and 29.7% of families are below the poverty line. Out of the total people living in poverty, 55.4% are under the age of 18 and 20.9% are 65 or older.