Increased consumption of whole grain products has been associated with decreased risk of health problems such as cardiovascular disease, diabetes and obesity. Phytate however, has always been a matter of concern, since it chelates minerals such as iron. Sangak is a very popular Iranian flat bread invented ca. five hundred years ago, made from 95% extraction flour. The bread is fermented but usually fermentation is not able to remove all phytate of the dough. In this study flours were first debranned; resulting bran was subjected to a hydrothermal process. The hydrothermaled (HT) brans were then incorporated in the Sangak flour. In the next step chemical, rheological and microstructural characteristics of Sangak flour, dough and bread prepared from two Iranian wheat varieties, Tajan and Back Cross of Roshan were investigated. Results indicated a reduction in phytate up to 55% in the samples. The resulting dough containing HT bran showed a higher development time and valorimetric value and was more stable than doughs made with normal bran. Dough made with HT bran showed a kind of protein matrix in which proteins and starch granules are oriented in a more non-ordered structure and more porosity in bread texture. It also had more UPP% (unextractable Polymeric Protein) and better fundamental rheological measurements than doughs made with normal bran. Key Words: Hydrothermaled bran, Sangak bread, Microstructure of bread, Dough rheology