The invention discloses an ecological benefit and 
mixed culture method of 
sipunculus nudus. According to the ecological benefit of the 
sipunculus nudus disclosed by the invention, the effect of the 
sipunculus nudus on improving the breeding 
ecological environment is researched, the situations that the sipunculus nudus has a migration effect on organic matters of sediments and also has biological disturbance behaviors are found, and the physical and chemical characteristics of the sediments and 
sediment-water interfaces can be improved. The sipunculus nudus is in 
mixed culture in a pond with a sandy bottom or a 
silt bottom, so that the substance 
utilization rate of a breeding 
system can be increased, and besides, the breeding 
water body environment is improved. According to the 
mixed culture method disclosed by the invention, the sipunculus nudus and 
penaeus monodon can be in the mixed culture on the basis of a good scientific basis and good practical data, for example, the sipunculus nudus and the 
penaeus monodon have similar requirements for temperature, 
salinity and the like; besides, meshes are covered, so that the probabilitythat the 
penaeus monodon preys on the sipunculus nudus can be obviously reduced; the breeding functions of the sipunculus nudus and the 
penaeus monodon have a complementary relationship. The situation that the sipunculus nudus is unceasingly bred for 60-80 days after the 
penaeus monodon is harvested so as to solve problem that the breeding cycle of the sipunculus nudus and the breeding cycle of the 
penaeus monodon are not incompletely synchronous is also found.