The invention provides a method for preparing modified nano catalytic zinc oxide antimicrobial ceramic. The method is characterized in that a sterile antibacterial agent which is the modified nano catalytic zinc oxide antimicrobial liquid or powder is added in glaze, the multifunctional ceramic glaze is prepared. The prepared antimicrobial ceramic has the advantages of antibiosis and mildew-resistant functions, and has the advantages of fast disinfection effect, strong bactericidal activity, good endurance, no secondary pollution, good stability, deodorization, negative ion releasing, and far-infrared health care, the antibacterial rate can reach 99.99%, the mildew-resistant level is 0 grade, and the released negative ions is 1500/cm<3>. The prepared ceramic can be widely used; distortion or discoloration on the surface of the ceramic cannot be generated; the antibacterial action can be effectively performed for long term; zinc oxide and ceramic basic glaze can be easily mixed; under natural illumination, and the modified nano catalytic zinc oxide can perform multiple functions of antibiosis mildew-resistance, deodorization, negative ion releasing, and far-infrared health care.