Gravity separation (jigging) and flotation were used to upgrade barite ore from the under developed Mehdi-Abad deposit with general specific gravity (S.G) 3.59 gr/cm3. Jigging experiments on coarse particles did not indicate significant upgrading (S.G 3.94 gr/cm3 and recovery 90%) where barite particles are mainly liberated in fine size fractions (-175µm). Optimized flotation parameters were selected based on results of designed experiments: Na-dodecylsulphate (collector) 750 g/t, sodium silicate (depressant) 2000 g/t, pH 9, size -106+63µm, conditioning time 4 min. Results of flotation tests based on optimized parameters (S.G 4.31 gr/cm3, recovery 94%) showed substantial improvement in comparison with jigging results.