Abstract: The present invention discloses an apparatus and method for disinfecting an object in a batch, continuous, or mixed mode. The apparatus according to the present invention comprises a bath to/from which water is flowed in/drained out; and at least one ultraviolet ray (UV) lamp unit assembly mounted in the bath, each UV lamp unit assembly including a plurality of UV lamp units. Each UV lamp unit comprises a quartz tube, a UV lamp mounted in the quartz tube and a photo-catalyst layer of titanium dioxide formed on an outer surface of the quartz tube to disinfect an object in the bath by the photo-catalytic reaction of titanium dioxide and UV. The apparatus of the present invention may comprise a conveyer device comprising a driving roller, driven rollers and a conveyer belt wound around the rollers, the conveyer device is divided into an inlet portion formed at a first outside of the bath, a conveying portion formed in water in the bath and a discharging portion formed at a second outside of the bath.