Mlakva is located in the municipality Perušić, in Lika-Senj County at an elevation of 559 meters above sea level and it covers the area of 20.58 km² (7.95 sq. miles). According to the 2011 census report, there were 50 inhabitants. It is largely populated by Serbs (86%), but also Croats (14%). Nearby places: Gornji Kosinj, Kruščica, Krš, Rudinka, Vukelići, Studenci, Mezinovac, Kaluđerovac, Klenovac and Vaganac.