Qalnigi Denuch'dnel'usht is a island located in Matanuska-Susitna County, Alaska. It appears on the Tyonek B-2 SW USGS 7.5-minute topographic quadrangle. The elevation at this location is approximately 19.50 feet (5.94 m) above sea level. The nearest populated place is Alexander, approximately 5.4 miles to the N.