Abstract: The purpose of the present invention is to provide a liquid supply device and biological cleaning device that, by supplying a sterile liquid including low-flow, low-pressure microbubbles, can dramatically increase cleaning effects and clean quickly and neatly without damaging a biological tissue. A liquid supply device 3, having a supply flow path 2 for supplying a liquid containing microbubbles to a cleaning instrument 1 for cleaning an organism and to a cleaning target such as a medical instrument, is characterized by being provided with a tube pump 5 for delivering the liquid to the supply flow path 2 and a microbubble generator B that is provided midway on the supply flow path 2 and is for causing microbubbles to be generated in the liquid.