The feasibility of co-culturing the sea cucumber Holothuria leucospilota Brandt in a subtropical fish farm was investigated in a field study. Sea cucumbers were cultured in the fish farm in cages suspended at 4 m deep (suspended culture) and directly on the seafloor (bottom culture). The survival and growth of the sea cucumbers were monitored twice during the 3-month, summer experimental period (May 26–August 14, 2010). Results showed that the suspension-cultured sea cucumbers exhibited excellent survival rate (100%) during the whole study period. There also occurred no mortality in the bottom-cultured sea cucumbers during the first culture period (May 26–July 13); but all these died from anoxia caused by water column stratification during the second culture period (July 14–August 14). The specific growth rate of the bottom-cultured sea cucumbers (1.05 ± 0.21 % day−1) was nearly double that of the suspended culture animals (0.57 ± 0.21 % day−1) during the first culture period, and the growth rates of the suspended culture sea cucumbers in the second culture periods (0.46 ± 0.24 % day−1) was only a little lower than that of the first period. The sea cucumbers H. leucospilota could ingest and assimilate sediment with high organic matter content with an average assimilation efficiency of 14.9 ± 3.9%. This study indicated that fish farm detritus can be effectively used as a food source for the sea cucumber and that it can be turned into a valuable secondary crop in the form of the sea cucumber biomass.