"Glass wool" and "rock wool" had been used as sound absorbing materials over several decades because they have excellent sound absorbing properties as well as being very productive and economical. Unfortunately, they were found to be toxic because of flying glass whiskers. To replace glass wool and rock wool as the sound absorbing panels, the recycled glass powders with zeolite and Na2SiO were foamed, adding foaming agents such as NaOH and CaCO3 at different foaming temperatures and time in an electrical furnace. Recycled glass powders from crushed passenger car window were heated up to 720 degrees C in an electrical furnace for an optimal foaming condition. The compressive strength of the foamed glasses was measured using a dynamic materials tester. On the basis of microstructure observation of the foamed glasses, the excellent sound absorbing materials was tried to be fabricated by measuring the sound absorbing coefficient of the foamed glass materials by adding various amounts of NaOH and water.