Bread is a staple food in human diet. Among the Iranian breads, the Sangak bread has a distinguish quality and nutritional value. Fresh bread has a short shelf life and its quality decreases with increasing the time between baking and consumption due to staling. Baking is one of the main processes in bread making that affects the bread quality and staling. Many phenomena such as evaporation, dough volume rising, starch gelatinization, protein denaturation and crust forming occur in baking. In this research, the impact of baking duration on the bread quality was studied. In the first stage, the effect of baking time on the qualitative parameters of Sangak bread such as pores distribution, apparent volume, density and water activity of bread, stiffness of bread, and crust color were determined. The obtained results showed that increasing the baking time reduces the moisture content, water activity, volume, porosity and L value, but increases density, a and b values and bread stiffness. In the second stage of this study, thermal conductivity, one of the most important thermophysical properties, of the Sangak bread during baking was determined and modeled. A line-heat source probe was used to measure thermal conductivity. The results indicated that thermal conductivity decreases during baking with increasing the porosity and decreasing the moisture content of bread. To model the thermal conductivity, four predictive models for porous food were selected and developed (series, parallel , Krischer and Maxwell models). The effective thermal conductivity predicted by Krischer model was in good agreement with the experimental data. Keywords: Thermal Conductivity, Porosity, Water Activity, Moisture Content, Color, Volume, Dencity, Staling.