Maquoketa () is a city in Jackson County, Iowa, United States. Located on the Maquoketa River, it is the county seat of Jackson County.
U.S. Route 61 adjoins the city, which therefore hosts traffic between Dubuque and the Quad Cities. Iowa Highways 62 and 64 also pass through the city. Maquoketa Caves State Park is located a few miles northwest of Maquoketa.
The population in 2019 was 5,990 according to the United States Census Bureau and was 6,141 at the 2010 census.
Maquoketa was originally called Springfield, and under the latter name was laid out in 1838. The present name, after the Maquoketa River, was adopted in 1844. The river's name derives from Maquaw-Autaw, which means "Bear River" in Meskwaki.
The Davenport and St. Paul Railroad was extended to Maquoketa in 1870 prompting growth. The county seat was transferred from Andrew to Maquoketa in 1873.
As of the census of 2010, there were 6,141 people, 2,655 households, and 1,612 families residing in the city.