There has been increasing interest of alginate gel utilization for environmental application. This study was aimed to investigate influence of sodium alginate and barium chloride concentrations on mechanical and chemical stabilities of the barium alginate gel. The barium alginate beads were mechanically tested using universal testing machine while the beads were soaked in the solutions with pHs of 5 to 9 or salts (sodium chloride, potassium chloride, and sodium hydrogen carbonate) for chemical stability test. The result showed that concentrations of barium chloride and sodium alginate obviously affected mechanical and chemical stabilities. Higher barium chloride concentrations decreased stress and Young’s modulus of beads whereas higher alginate concentrations resulted to higher gel strength and flexibility. The stress and Young’s modulus of 0.57 and 37.71 MPa were found in the best preparation condition (barium chloride of 1% and sodium alginate of 5%). For the chemical tests, the gel beads mostly tolerated in the solutions with different pHs and salt solutions excluding NaHCO3. The gel beads prepared in this work sound potential for practice.