Abstract: Apostichopus japonicus, which belongs to Echinodermata, Holothuroidea, Apostichopus, is a valuable edible sea cucumber in Eastern Asia. Artificial cultivation of A. japonicus has developed rapidly to meet consumer demand and cope with the rapid decline of fishery resources caused by over-exploitation and environmental pollution. However, various diseases lead to high mortality of A. japonicus, impacting the sustainable and rapid development of aquaculture. The low genetic diversity and few high-quality economic varieties in traditional culture can also restrict the development of A. japonicus aquaculture. Green eco-ranching development based on the habitat of A. japonicus is thus important. Seagrass bed is one of the most important shallow-marine ecosystems. Zostera marina, which distribute widely in Northern China, is a natural habitat for A. japonicus. Z. marina can be a food source for A. japonicus due to its rich food resource such as organic debris, bacteria, prokaryotes living on seagrass leaves, rhizomes, and rhizospheres. Z. marina can improve the immunity of A. japonicus. Non-specific immune-related enzyme activities of A. japonicus with ingestion of Z. marina could be improved. However, there is few studies on habitat selectivity and physiological response of A. japonicus to Z. marina. We conducted experiments to investigate the selectivity, behavioral responses and physiological status of A. japonicus to different habitats. We studied the habitat selection of A. japonicus by calculating the mean attractive rate. We counted the crawling frequency and tentacles activity frequency, and measured the length and thickness of feces of A. japonicus to determine the activity of movement, feeding and digestion of A. japonicus in different habitats. Under indoor simulated environmental conditions, the selection of A. japonicus to Z. marina, bare sand and stone habitats was studied. The average aggregation rate, behavioral characteristics (crawling, feeding and excretion behavior) and physiological status (ATP content in muscle of A. japonicus; dopamine, adrenergic, norepinephrine and cortisol contents in coelomic fluid of A. japonicus) in different habitats were compared and analyzed. The results showed that: 1) A. japonicus preferred the Z. marina habitat significantly higher than bare sand habitat and stones habitat. The average aggregation rate of A. japonicus in the Z. marina habitat reached 64%, which was 4.5 times higher than that in bare sand habitat. 2) The activity of sea cucumbers in Z. marina habitat was significantly higher than those in stones and bare sand habitats, and the frequencies of crawling and feeding were 2 times higher than those in stones habitat. In Z. marina habitat, the feces length and thickness of A. japonicus was 1.9 and 2.5 times higher than those in bare sand habitat. 3) In Z. marina habitat, the content of ATP in muscle was 2 times higher than that in stones habitat and bare sand habitat. The results showed that A. japonicus had obvious selection to the habitat of Z. marina, which are active in the habitat of Z. marina and in good physiological status, indicating that the Z. marina bed is a high-quality habitat for the construction of green ecological pasture for A. japonicus.