Olive Branch is a city in DeSoto County, Mississippi, United States. It is the ninth largest city in Mississippi. Olive Branch is a suburb of Memphis, Tennessee. The city is situated at the intersection of the U.S. Highway 78 freeway and Mississippi State Highway 302 (known locally as Goodman Road). The population was 21,054 at the 2000 census. Estimates now show a population exceeding 30,000. Along with other fast growing suburban cities in DeSoto County, Olive Branch attributes most of its growth and development to the exodus of large numbers of middle-class families from central Memphis (white flight).

As of the census^GR2 of 2000, there were 21,054 people, 7,546 households, and 6,036 families residing in the city. The population density was 581.7 people per square mile (224.6/km²). There were 7,935 housing units at an average density of 219.2/sq mi (84.7/km²). The racial makeup of the city was 86.60% White, 11.30% African American, 0.20% Native American, 0.41% Asian, 0.75% from other races, and 0.73% from two or more races. Hispanic or Latino of any race were 1.46% of the population.

There were 7,546 households out of which 42.8% had children under the age of 18 living with them, 65.8% were married couples living together, 10.6% had a female householder with no husband present, and 20.0% were non-families. 16.3% of all households were made up of individuals and 5.1% had someone living alone who was 65 years of age or older. The average household size was 2.78 and the average family size was 3.13.

In the city the population was spread out with 29.5% under the age of 18, 6.8% from 18 to 24, 34.7% from 25 to 44, 20.0% from 45 to 64, and 8.9% who were 65 years of age or older. The median age was 33 years. For every 100 females there were 96.4 males. For every 100 females age 18 and over, there were 92.9 males.

The median income for a household in the city was $55,187, and the median income for a family was $60,851. Males had a median income of $42,288 versus $28,287 for females. The per capita income for the city was $22,680. About 3.9% of families and 5.2% of the population were below the poverty line, including 7.2% of those under age 18 and 5.6% of those age 65 or over.The City of Olive Branch is served by the DeSoto County School District.