Linneus is a small town in Linn County, Missouri, United States. The population was 369 at the 2000 census. It is the county seat of Linn County. Originally Linnville, its name was changed to honor Carl Linnaeus in 1840.
Linneus is located at 39°52′41″N 93°11′16″W / 39.87806°N 93.18778°W / 39.87806; -93.18778 (39.878082, -93.187813). According to the United States Census Bureau, the city has a total area of 1.1 square miles (2.8 km²), all of it land.
As of the census of 2000, there were 369 people, 153 households, and 98 families residing in the city. The population density was 341.0 people per square mile (131.9/km²). There were 166 housing units at an average density of 153.4 per square mile (59.3/km²). The racial makeup of the town was 98.37% White, 1.08% African American, 0.27% Asian, 0.27% from other races. Hispanic or Latino of any race were 0.27% of the population.