One of the contaminants of industrial wastewater is hardness, which has harmful effects on our environment when discharge to surface water. Hence, various treatment methods have been studied to remove the hardness of wastewater. Herein, a series of oxide glasses with different compositions were prepared as novel adsorbents to dispose of hardness from industrial wastewater via adsorption treatment technique. It is found that the treatment with borosilicate glass (25% B2O3–20% SiO2 – 5% CuO – 5% Bi2O3 – 45% Na2O) exhibits the highest hardness removal efficiency. Based on such sample, the boundary conditions, including contact time, temperature, and adsorbent dosage are controlled to obtain the optimum removal efficiency. The optimum boundary conditions are found to be 150 min, and 15g L-1 for contact time, and adsorbent dosage, respectively. Fortunately, the efficiency is unaffected by the temperature of the adsorption process, which indicates no required expended energy and low cost water treatment. The effect of initial hardness concentration and pH of wastewater shows an initial increase in the removal efficiency to a maximum value at 150 mg L-1 and 6.5 – 7.2, respectively. The results from the contact time study were simulated by Langmuir and Freundlich isothermal adsorption models, and well fitted. Finally, the comparison with the previous studies shows that the experimental results exhibit excellent and acceptable hardness removal efficiency at the appropriate contact time and adsorbent dosage.