Originally known as Savage Crossing, Keiser was one of several cities established by prominent late-19th century planter and land developer Robert E. Lee Wilson. The city, which served as a logging outpost and railroad stop on the rail line that connected Wilson and Jonesboro, was named for Wilson's friend, John Keiser. After the forests had been cleared, the city transitioned from a logging town to an agrarian community. The Arkansas Agricultural Experiment Station established a research farm near Keiser in 1957, and built a regional headquarters in Keiser, the Northeast Research and Extension Center, 1980.
As of the 2010 United States Census, there were 759 people living in the city. The racial makeup of the city was 92.0% White, 5.1% Black, 0.4% Native American, 0.1% Asian, 0.4% from some other race and 0.9% from two or more races. 1.1% were Hispanic or Latino of any race. As of the census of 2000, there were 808 people, 303 households, and 230 families living in the city. The population density was 2,239.3 people per square mile. There were 334 housing units at an average density of 925.7/sq mi. The racial makeup of the city was 92.45% White, 4.46% Black or African American, 1.73% Native American, 0.99% from other races, and 0.37% from two or more races. 2.85% of the population were Hispanic or Latino of any race. There were 303 households, out of which 32.3% had children under the age of 18 living with them, 62.7% were married couplesliving together, 8.6% had a female householder with no husband present, and 23.8% were non-families. 20.8% of all households were made up of individuals, and 11.9% had someone living alone who was 65 years of age or older. The average household size was 2.67 and the average family size was 3.05. In the city, the population was spread out, with 26.5% under the age of 18, 6.2% from 18 to 24, 28.0% from 25 to 44, 26.1% from 45 to 64, and 13.2% who were 65 years of age or older. The median age was 38 years. For every 100 females, there were 92.8 males. For every 100 females age 18 and over, there were 94.1 males. The median income for a household in the city was $35,517, and the median income for a family was $36,940. Males had a median income of $27,679 versus $19,500 for females. The per capita income for the city was $14,769. About 10.4% of families and 10.8% of the population were below the poverty line, including 9.7% of those under age 18 and 21.8% of those age 65 or over.
