Abstract: This experiment was conducted to study the localization of IgA and IgG in porcine respiratory tract. The tissue samples of soft palatine tonsil, pharyngeal tonsil, trachea and lung were collected from pigs (50 days) and studied by immunohistochemistry methods for detection of the IgA and IgG secreting cells in porcine respiratory tract. The results showed that the IgA and IgG secreting cells in soft palatine tonsil were distributed mainly underneath the crypt epithelium. In pharyngeal tonsil, the secreting cells were predominantly found underneath the mucosal epithelium. In trachea, the secreting cells were observed just beneath the mucosal epithelium. Some were also found around the tracheal glands. A few IgA secreting cells were found between the tracheal epithelium. In lung, the secreting cells were located in alveolar septum, and underneath bronchus and bronchiole epithelium. In addition, the secreting cells in lung stained much lighter than that in trachea. Statistics analysis showed that the number of IgA secreting cells was the most in trachea, then the pharyngeal tonsil, the soft palatine tonsil, the lung had the least number of IgA secreting cells. However, the number of IgG secreting cells were the most in pharyngeal tonsil, then the trachea, the lung, the soft palatine tonsil had the least number of IgG secreting cells. Such a wide distribution of the IgA and IgG secreting cells in porcine respiratory tract provide a foundation and knowledge to respiratory mucosa immunity and pathogenesis study on the pig′s disease.