Keiser is a city in Mississippi County, Arkansas, United States. The population was 759 at the 2010 census.
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.
Keiser is located at 35°40′28″N 90°5′46″W (35.674411, -90.096084). The city is concentrated along a stretch of Arkansas Highway 181 southwest of Osceola and northwest of Wilson. Interstate 55 passes just east of the city.
According to the United States Census Bureau, the city has a total area of 0.4 square miles (1.0 km2), all land.
The climate in this area is characterized by hot, humid summers and generally mild to cool winters.