Abstract: The Dragon's Blood (DB) as a traditional Chinese medicine has shown potential in protecting aerospace physiological injury. However, its mechanism on gut protection has not been elucidated. P-glycoprotein (P-gp) as an efflux transporter can transport toxins and harmful bacteria out for intestinal epithelial cells to maintain the intestinal barrier integrity. In this paper, a rat tail-suspension model was used to simulate microgravity (SMG) and the DB was orally administered to rats for 21 days. After this, several processes were carried out, observing the jejunum tissue morphology, determining the intestinal barrier permeability markers, and detecting the expression form of P-gp and Wnt/β-Catenin signaling pathway related proteins. The results show that DB can promote the expression of P-gp gene and protein in jejunum by activating Wnt/β-Catenin signaling pathway, alleviating rat jejunum barrier injury in 21d-SMG rats. The study results can provide a research basis for gut protection of astronauts during spaceflight.