Barium monoxide wani fili ne na inorganic wanda ya ƙunshi abubuwan barium da oxygen, tare da tsarin sinadarai BaO. Wani fari ne mara wari wanda za'a iya samuwa ta hanyar dumama barium carbonate ko barium nitrate a gaban wakili mai ragewa. Barium monoxide wani sinadarin oxide ne na asali kuma ana amfani dashi a aikace-aikacen masana'antu daban-daban, gami da samar da wasu nau'ikan gilashi, kayan yumbu, da kuma azaman mai kara kuzari a wasu halayen sinadarai. Ana kuma amfani da shi wajen kera sinadarin barium oxide sulfide phosphor da ake amfani da shi wajen kera bututun ray na cathode na talabijin da na’urorin kwamfuta.