South Lineville is a village in Mercer County, Missouri, United States.

The name Lineville refers to the fact the town site lies near the Missouri—Iowa state line.

[5] The village is located directly south of its twin city of Lineville, Iowa.

According to the United States Census Bureau, the village has a total area of 0.06 square miles (0.16 km2), all land.

38.5% of all households were made up of individuals, and 15.4% had someone living alone who was 65 years of age or older.

There were 20.0% of families and 15.8% of the population living below the poverty line, including no under eighteens and 28.6% of those over 64.