TheNišava District (Serbian:Нишавски округ,romanized: Nišavski okrug,pronounced[nîʃaʋskiːôkruːɡ]) is one ofadministrative districts ofSerbia. It lies in thesoutheastern parts of Serbia. According to the 2022 census, it has a population of 343,950 inhabitants. The administrative center of the district is the city ofNiš. AfterSouth Bačka District, it is the second largest District in Serbia.