Winthrop is a city in Little River County, Arkansas, United States.

[3] Winthrop is located in northwestern Little River County 20 miles (32 km) northwest of Ashdown, the county seat, and 7 miles (11 km) east of the Oklahoma border.

According to the United States Census Bureau, the city has a total area of 1.0 square mile (2.7 km2), all land.

25.4% of all households were made up of individuals, and 14.1% had someone living alone who was 65 years of age or older.

About 14.3% of families and 16.7% of the population were below the poverty line, including 15.6% of those under the age of eighteen and 9.1% of those 65 or over.