The release of protons and copper ions from microporous glass-ceramics, with a skeleton of Nasicon-type copper titanium phosphate crystal, into aqueous solution was investigated. When the materials were soaked in a solution containing Na+ ions, protons and copper ions were released gradually. Initially, the release proceeded with the exchange of H+ ions in the crystal for Na+ ions in the solution. The amounts released could be controlled effectively by doping the Nasicon-type crystal with Ca2+ ions. The glass-ceramics showed excellent bacteriostatic activity. These glass-ceramics are novel materials that can automatically control the release of bacteriostatic and fungistatic ions in response to the amount of Na+ ions in the environment.