The invention discloses a shelter and a method for mixed culture of octopus ocellatus and sea cucumbers. The shelter mainly consists of a skeleton and a polyethylene net attached to the skeleton, and the skeleton and the polyethylene net can be folded to be stored. The mixed culture method mainly comprises manufacturing of a shelter, layout of the shelter in a sea cucumber culture pond, elimination of harmful organisms in the pond, proper throwing opportunity of young octopus ocellatus and proper throwing density. The characteristic that the octopus ocellatus and the sea cucumbers do not eat each other and do not interfere with each other is utilized, and octopus ocellatus reefs can be used as shelters for young octopus ocellatus and adult octopus ocellatus; according to the relationship of a food chain in the pond, the advantage that rich copepoda and small shrimp and crabs in the sea cucumber culture pond can be used as baits of octopus ocellatus in different stages is utilized, so that the growth speed of octopus ocellatus is high, the survival rate is high, and the economic benefit of the sea cucumber culture pond in unit area is improved.