Its county seat is Sioux Falls,[2] South Dakota's most populous city.

[4] Minnehaha County is part of the Sioux Falls Metropolitan Statistical Area, the state's largest.

Minnehaha County lies on the east side of South Dakota.

The Big Sioux River flows south-southeast through the east central part of the county.

Its terrain consists of rolling hills, devoted to agriculture except around built-up areas, and dotted with lakes and ponds in its western portion.

[7] Source:[5] As of the 2020 census, there were 197,214 people, 78,715 households, and 48,690 families residing in the county.

In terms of ancestry, 43.8% were German, 17.7% were Norwegian, 11.6% were Irish, 6.8% were Dutch, 6.3% were English, and 3.2% were American.