Abstract: From viewpoint of back to the origin for reference and biogenetic law of ontogeny repeats phylogeny, this paper explores the essence and behavior characteristics of nature-tourism from angles of social biology, anthropology, philosophy and psychology. Research shows that the essence of nature-tourism is essentially primitive, atavistic and regressive. It leads to four behavior characteristics of nature-tourism: treasuring experience but not visiting, valuing process but not result, not taking convenience as condition, having the consciousness of treat nature friendly.