Background: Chronic bronchial inflammation underlies asthma, which is a complex disease with varied and largely reversible blockage of the respiratory route. Asthma is a major public health issue that affects people of all ages around the world. Many countries are seeing an increase in the prevalence of this disease, particularly among children. Among children, asthma is the most frequent long-term condition, accounting for more than half of all missed school days, emergency room consultations, and hospitalizations. Surfactant Protein D, a pattern-recognition molecule, dampens elevated levels of particular antibodies, alveolar macrophage accumulation, eosinophilia, and subepithelial fibrosis and mucous metaplasia, as well as airway hyper-reactivity in allergic asthma in vivo. Objective: In order to discover the connection between children's bronchial asthma and surfactant protein D. Conclusion: Salivary SP-D is a simple, low-cost, quick, and noninvasive way to collect saliva from children. Salivary SP-D levels may be linked to asthma exacerbation severity and peripheral airway resistance.