The present invention provides: an antibacterial/antiviral composition which has excellent antibacterial/antiviral activity under visible light irradiation； an antibacterial/antiviral agent； a photocatalyst； and a bacteria/virus inactivation method. An antibacterial/antiviral composition according to the present invention contains titanium oxide on which both a divalent copper compound and a silver compound are loaded. An antibacterial/antiviral agent according to the present invention and a photocatalyst according to the present invention contain an antibacterial/antiviral composition according to the present invention. A bacteria/virus inactivation method according to the present invention inactivates bacteria and a virus with use of an antibacterial/antiviral composition according to the present invention, an antibacterial/antiviral agent according to the present invention or a photocatalyst according to the present invention.本發明係提供一種在可見光照射下的抗菌‧抗病毒活性優良的抗菌‧抗病毒性組成物、抗菌‧抗病毒劑、光觸媒及菌‧病毒失活化方法。本發明之抗菌‧抗病毒組成物係包含共擔持有二價銅化合物及銀化合物的氧化鈦。本發明之抗菌‧抗病毒劑及本發明之光觸媒係含有本發明之抗菌‧抗病毒組成物。本發明之菌‧病毒失活化方法係使用本發明之抗菌‧抗病毒組成物、本發明之抗菌‧抗病毒劑或本發明之光觸媒使菌及病毒失活化。
