Abstract： Under the guidance of theory of diseases caused by latent dampness， this article is to explore the etiology and pathogenesis of chronic rhinosinusitis （CRS） in children and its diagnosis and treatment. The latent dampness is characterized by insidious onset，long process，and deficient healthy qi without controlling pathogens. Its connotation is that the healthy qi is deficient with latent pathogens and the dampness is hidden in the body，which is the pathogenic factor that triggers the CRS onset in children. The main etiology of latent dampness-induced CRS in children is constitutional peculiarities，improper diet，emotional disorders，and chronic latent pathogens leading to pathological changes. Latent dampness is not immutable in the body，and may be accompanied by or change into other pathogens. The synergistic pathogenesis results in complicated conditions. Against the characteristics of CRS in children， it is divided into acute phase，lingering phase and remission phase. Tonifying qi to reinforce the healthy qi and banking up earth to eliminate dampness is the treatment principle. According to the three different stages，the core ideas of venting and dissipating latent pathogens， treatment with both attack and supplementation， and resolving deficiency and impairment by supplementing and boosting are used to guide the prescription of medications. Attention is paid to the combination of prevention and treatment to reconstruct the balance of healthy qi and pathogens in the body so that the new ideas for the prevention and treatment of CRS in children with Chinese medicine are provided.