Abstrac :
GIS has sufficient capacity in finding thermal Agro-climatic regions for barley crop in Iraq, thus managed this technique (gis) represent quantum this information in subjective Maps and high accuracy and easily analytical. Iraq is characterized by spatial variation in maximum and minimum temperature ranging from (63.18 and 81.24) and (43.6 and 57.12 m) for Mosul and Basra stations respectively.
Very high investment for the barley crop has emerged in the province of Mosul while very low investment in Anbar, Karbala, Najaf and Basra.
The study found after congruence between thermal Agro-climatic regions maps of barley crop that the ideal province appears separately in northern Iraq, represented by central parts of north and west and small area of in the east of study area with 78.39367 km (96.9%) of the area of the study area.
Either extreme province appeared separately in parts of north-west and part of the Midwest and parts of the east of the center with an area of 48.43752 (06.11%) of the study area.
And Medium thermal climate, including most of the provinces of Iraq ,from the north to center and a wide in the south with an area of 5.312322 km (98.78%) of the study area, which means that most of the Iraqi provinces have Medium thermal climate for the cultivation of the crop covered most provinces of Iraq in connection of the north, center and a ample in the south, which means that most of Iraq's provinces have a Medium thermal climate for the cultivation of the crop.
