Wadena County is a county located in the U.S. state of Minnesota. As of 2000, the population is 13,713. Its county seat is Wadena.
According to the U.S. Census Bureau, the county has a total area of 1,406 km² (543 mi²). 1,386 km² (535 mi²) of it is land and 21 km² (8 mi²) of it (1.47%) is water.
