Lake Johanna is a lake in Ramsey County, in the U.S. state of Minnesota.
It was named after Johanna McKenty, an early settler.
Fish species in the lake include black crappie, bluegill, bowfin (dogfish), green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, tiger muskellunge, walleye, white sucker, yellow bullhead, yellow perch.