Indian River County is a county located in the southeastern and east-central portions of the U.S. state of Florida.

As of the 2020 census, the population was 159,788. Its seat is Vero Beach. It is Florida's 7th richest county and in 2000 was the 87th richest county in the U.S. by per capita income.

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In 1905 St. Lucie County was formed from the southern portion of Brevard County; in 1925 Indian River County was formed from the northern portion of St. Lucie County. It was named for the Indian River, which runs through the eastern portion of the county.

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According to the U.S. Census Bureau, the county has a total area of 617 square miles (1,600 km2), of which 503 square miles (1,300 km2) is land and 114 square miles (300 km2) (18.5%) is water.

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As of the 2020 United States census, there were 159,788 people, 60,959 households, and 37,647 families residing in the county.