塔纳湖（阿姆哈拉语：ጣና ሐይቅ，拉丁化：Ṭānā Hāyḳ）是青尼罗河的发源地，也是埃塞俄比亚最大的湖泊，位于国家西北部海拔1,840公尺的高地(12°0′N 37°15′E / 12.000°N 37.250°E / 12.000; 37.250)，长度约84公里，阔度约66公里，最深深度为15公尺。塔纳湖的水从Reb River和Gumara River注入，湖泊面积视乎季节和雨量，一般为3,000至3,500平方公里。在塔纳湖流出蓝尼罗河的地方建成水堰后，湖泊水位受到控制，也能调节水流进入提斯·阿贝(Tis Abay)瀑布和水力发电厂。

Lake Tana (also spelled T'ana, Amharic:ጣና ሐይቅ, Ṭana Ḥäyq, T’ana Hāyk’; an older variant is Tsana, Ge'ez ጻና Ṣānā; sometimes called "Dembiya" after the region to the north of the lake) is the source of the Blue Nile and is the largest lake in Ethiopia. Located in Amhara Region in the north-western Ethiopian Highlands, the lake is approximately 84 kilometers long and 66 kilometers wide, with a maximum depth of 15 meters, and an elevation of 1,788 meters. Lake Tana is fed by the Lesser Abay, Reb and Gumara rivers; and its surface area ranges from 3,000 to 3,500 km,² depending on season and rainfall. The lake level has been regulated since the construction of the control weir where the lake discharges into the Blue Nile. This controls the flow to the Blue Nile Falls (Tis Abbai) and hydro-power station.