Aquaporin 5 (AQP5) in nasal mucosal epithelial cells is an important hub protein for maintaining local water metabolism and barrier function. Its abnormal distribution and expression can lead to the obstruction of the transportation and transformation of body fluids, keeping allergic rhinitis (AR) in a hyper-secretory state for a long time. The defensive yang transformed by spleen yang, as the first line of defense on the human body surface, has highly similar functions in defending against exogenous pathogens and water transportation to those of AQP5. The traditional Chinese medicine treatment of warming yang and invigorating the spleen can inhibit the activation of the NF-κB pathway and up-regulate the expression of AQP5, thus effectively improving the clinical symptoms and immune indexes of AR with spleen-yang deficiency. Therefore, the abnormal regulation of AQP5 in nasal mucosal epithelial cells may be a key entry point for the study of the essence of AR spleen-yang deficiency syndrome.