Tafkin Kossou (Faransanci: Lac de Kossou) shine babban tabki na Cote d'Ivoire. Ya ta'allaka ne akan Kogin Bandama na tsakiyar kasar. Tafki ne na wucin gadi, wanda aka kirkira a cikin shekarata 1973 ta hanyar lalata Kogin Bandama a Kossou (Dam ɗin Kossou). Kimanin mutanen Baoulé 75,000 suka yi gudun hijirar ta tafkin. Tafkin Kossou an kirkireshi ne bayan an gina madatsar ruwa ta Kossou a fadin kogin Bandama wanda aka kammala shi a shekarar 1973. An kammala aikin Dam din Kossou a karkashin kulawar shirin Majalisar Dinkin Duniya na Raya Kasa, hukumar da abin ya shafa itace Marubuciya de Valle du Bandama (ADV). Hakan ya hada da tsugunar da mutane kimanin 75,000 daga matsugunai 200, zuwa wasu sabbin kauyuka 54 wadanda kamfanin ADV ya gina, 32 a yankin dajin da kuma 22 a yankin savanna. An sake tsugunar da mutane 22,000 kafin a fara shigar da ruwa a cikin 1971. An gina madatsar ruwa daga ƙasa da dutse mai ƙwanƙwasa, kuma yana da tsayi kusan 1,500 m (5,000 ft). Tsibirin da aka kama yana da ikon samar da wutar lantarki mai karfin megawatt 174.