We worked out a new endonasal operation (Swinging of nasolacrimal duct and inferior turbinate) for chronic sinusitis and presented the theoretical ground and the outline of the operative procedure. In an immunohistochemical investigation, immune staininng of the mucous membrane of the inferior nasal turbinate and the mucous membrane around thenatural ostium was conducted using Monoclonal Mouse Anti-Human Mast Cell Tryptase (Daco-Mast Cell, AA 1). As a result of examination on the cases divided by the presence or absence of allergy involvement, it was found that there was no significant difference. It may be concluded from these results that this new operation is useful for chronic sinusitis irrespective of the presence or absence of allergy involvement.