To observe the effects of electroacupuncture at "ST36" and "BL20" on water metabolism and intestinal mucosal permeability in colon tissue of rats with spleen deficiency and dampness-containing type ulcerative colitis (SDDR-UC) and to investigate its mechanism of action. 60 SD rats were randomly divided into 4 groups: normal group, model group, non-meridian non-acupuncture group and non-meridian non-acupuncture group, electroacupuncture group and non-meridian and non-acupoint group. The normal group was fed normally, and the other three groups were replicated the SDDR-UC model using the method of combining disease and evidence. In the electroacupuncture group, the "ST36" and "BL20" were selected, and in the non-meridian and non-acupoint group, the non-meridian and non-acupoint points were selected, and the intervention process lasted 20 min for 14 d. The general conditions of the rats were observed, and the body weights, grasping strengths, changes in the lengths of the colon, and the scores of the colonic mucous membrane damage index (CMDI) scores were measured. Hematoxylin-eosin staining (HE) method was used to observe the histopathological morphology of colon. Western blot (WB) method was used to detect the phosphorylation of mitogen-activated protein kinase (p38MAPK), extracellular signal-regulated kinase (), and aquaporin protein 4 (AQP4), immunohistochemistry (IHC) for ZO-1 and Occludin. Quantitative real-time PCR (RT-qPCR) for AQP4. Quantitative real-time PCR (RT-qPCR) method was used to detect AQP4 mRNA expression. The results show that compared with the normal group, rats in the model group and the non-transthoracic non-cavity group show decreased body weight, grasping power, colon length and increased CMDI score (P < 0.01). Colon tissues show pathological morphological manifestations such as inflammatory cell infiltration and crypt abscess, with decreased expression of AQP4, ZO-1 and Occludin (P < 0.01), and phosphorylation of p38MAPK, elevated (P < 0.05). Compared with the model group, rats in the electroacupuncture group show elevated body weight, grip strength, colon length, decreased CMDI score (P < 0.01), reduced inflammatory infiltration of colon tissue, relatively regular crypt margins, significantly higher expression levels of AQP4, ZO-1, Occludin (P < 0.01), and phosphorylation of p38MAPK, proteins significantly decrease (P < 0.05). Electroacupuncture of "ST36" and "BL20" may play an important role in improving water metabolism and intestinal mucosal permeability in SDDR-UC rats by inhibiting the phosphorylation of p38MAPK, and up-regulating the expression of AQP4, ZO-1 and Occludin.