Abstarct: Nowadays, the processing of low-grade ores such as shale bauxites have gained special importance due to the widespread use of aluminum mextal and its compounds and also the limited resources of this strategic mextal. Hence, the purpose of this research was focused on the investigation of the possibility of extracting alumina from low-grade bauxite (shale) of Jajarm using the sintering method and then its alkaline dissolution. For achieving this goal, firstly the influence of important parameters including the sintering temperature, C/S ratio, N/A ratio and Na2C concentration was investigated on the dissolution efficiency using response surface methodology. The results indicated that respectively Na2C concentration, sintering temperature and the interaction effect between Na2C concentration and N/A ratio had the greatest influence on the dissolution efficiency. As the dissolution efficiency increased with increasing the sintering temperature and reducing Na2C concentration. The effect of N/A ratio also showed that at high levels of leaching agent concentration (60 G/L), the dissolution efficiency increased with increasing N/A ratio and decreased with a gentle slope at low levels (30 G/L). In the next step, the optimization of influential parameters on the aluminum dissolution process were performed. Process optimization demonstrated that the maximum dissolution efficiency (about 78%) was obtained under the conditions: the sintering temperature of 1150 °C, C/S ratio of 2.09, N/A ratio of 0.90 and Na2C concentration of 30.65 G/L.