The invention discloses a water-saving sea cucumber culturing method, which comprises: selecting a culturing water source; treating pool water; treating feed; controlling a water change period; and controlling a culturing environment by using a bioecological method according to culturing water ecological principles, growth environment requirements of marine organisms, correlations among organismsand harmless culturing standards. The key technique is to add bdellovibrio bacteriovorus nectophore bacterial solution into water, soak the feed in bdellovibrio bacteriovorus nectophore bacterial solution and change the water in the pool every 40 days in a culture period. The method is a biological culturing method, is green, safe, environmentally-friendly and obvious in effect, can improve waterquality, promote the ingestion of sea cucumbers, improve immunity, promote growth and improve survival rate and has a bright development prospect. The method has a great significance for improving economic benefits, food safety and protecting human health.