Barley (Hordeum vulgare L.) and Wheat (Triticum aestivum L.) are the two most widely cultivated stable food cereal crops in the world. Barley and Wheat grain samples were collected and homogenized each from three selected kebeles in Guna Begemidr woreda, South Gonder Zone, Ethiopia and its processed food (bread) were prepared from it. The levels of essential metals (Mg, Fe, Mn and Zn) in barley, wheat grains and its processed food were determined by Atomic Absorption Spectrophotometer after 0.5 g barely, wheat and its processed food (bread) samples were digested using mixtures of 4 mL of HNO3, and 2 mL of HClO4 (4:2, v/v) at 200oC for 1:30 and at 1800 c for 1:10 hour respectively based on the optimized wet digestion procedure. The optimized wet digestion procedure was evaluated using spiking method and an acceptable percentage recovery was obtained. The mean metal concentration (mg/kg dry weight) in wheat and barley flour was: Mn (5.7), Fe (43.8), Zn (28), Mg (243.4) and Mn (5.6), Fe (44.2), Zn (10.4) and Mg (284.4) respectively. The levels of metal in wheat and barley flour samples determined in this study were found in the following decreasing order: Mg > Fe > Zn > Mn. Among the studied metals, Mg was the highest and Mn was the smallest in all samples. The levels of Fe, Zn, Mn and Mg in wheat and barley samples collected from three kebeles in Guna Begemidr Woreda were found to be less than the level approved by FAO/WHO. Keywords: Barley, Wheat, Processed Foods, Essential Metals, Atomic Absorption Spectrophotometry.