The abalone production in Taiwan has dropped down in recent years because of theserious bacterial infection, especially the Vibrio alginolyticus. The V. alginolyticus canbe easily brought to the abalone culture ponds by feeding seaweeds (Gracilariatenuistipitata). For preventing pathogenic Vibrio infection, this study aims to test thedisinfection effects on G. tenuistipitata by disinfectants or probiotic. Disinfectantsincluding sterilized seawater, fresh water, sodium hypochlorite or ozone are used to washthe seaweed. The growth of G. tenuistipitata and total bacteria and Vibrio counts aftervarious treatments are used to evaluate the suitable procedure for disinfection. Inaddition, the total bacteria and Vibrio counts within the abalone guts and in its culturewater after feeding the treated G. tenuistipitata are used to evaluate.