There is provided a mixed antibacterial glass which stably controls the silver ion elution amount from the antibacterial glass into the drain water in an air conditioning system, thereby effectively preventing the occurrence of microorganisms in the drain water.The mixed antibacterial glass achieves antibacterial effect by releasing silver ions, and contains an antibacterial glass which shows alkalinity when dissolved, and another antibacterial glass which shows acidity when dissolved, the silver ion elution amounts from the antibacterial glasses showing alkalinity or acidity being within certain ranges as measured under certain conditions, the compounding amount of the antibacterial glass showing alkalinity being from 10 to 100 parts by weight with reference to 100 parts by weight of the antibacterial glass showing acidity, and the total silver ion elution amount being within a certain range as measured under certain conditions.
