Isabel is a town in Dewey County, South Dakota, United States.

[6] Isabel was laid out in 1910, and named in honor of a certain railroad employee's daughter.

[7] According to the United States Census Bureau, the town has a total area of 0.91 square miles (2.36 km2), all land.

The racial makeup of the town was 75.6% White, 23.0% Native American, and 1.5% from two or more races.

The racial makeup of the town was 66.1% White, 33.1% Native American, 0.42% Pacific Islander, and 5.4% from two or more races.

About 28.3% of families and 36.8% of the population were below the poverty line, including 52.2% of those under the age of eighteen and 29.0% of those 65 or over.