Irob (Ge'ez: ኢሮብ) is one of the woredas in the Tigray Region of Ethiopia. This woreda is named after the Irob people, who are the predominant ethnic group living there. Located in the Misraqawi Zone at the eastern escarpment of the Ethiopian highlands, Irob is bordered on the south by Saesi Tsaedaemba, on the west by Gulomahda, on the north and east by the Endelli River which separates it from Eritrea, and on the southeast by the Afar Region. The administrative center of this woreda is Dawhan; other towns include Alitena, the former administrative center.
The woreda is traditionally divided into three parts: Buknite-Arae (the present Waraatele, Harze Sebaata, Agar Lekoma and Edamossa kebeles), Adgadi-Arae (the present Edalgeda kebele) and Hassaballa (the present Arae kebele). Elevations range from about 150 meters above sea level where the eastward-flowing Endelli leaves Irob to Mounts Asimba (3,250 meters) and Ayga. Landmarks in Irob woreda include the Assabol Dam near Dawhan, and the monastery of Gunda Gunde.
Both Irob woreda and its urban center of Alitena were occupied by the Eritrean army during the early months of the Eritrean-Ethiopian War. They reportedly inflicted a great amount of damage to Alitena.
Based on the 2007 national census conducted by the Central Statistical Agency of Ethiopia (CSA), this woreda has a total population of 25,471, an increase of 43.29% over the 1994 census, of whom 12,412 are men and 13,059 women; 2,091 or 8.21% are urban inhabitants. With an area of 1,532.64 square kilometers, Irob has a population density of 16.62, which is less than the Zone average of 56.93 persons per square kilometer. A total of 5,363 households were counted in this woreda, resulting in an average of 4.75 persons to a household, and 5,165 housing units. The majority of the inhabitants said they practiced Ethiopian Orthodox Christianity, with 55.99% reporting that as their religion, while 40.64% of the population were Catholics, and 3.31% were Muslim.