Early childhood caries (ECC) is recognized as an infectious disease. The first step in its development is primary infection by the bacterium S. mutans which has been identified as the primary etiologic factors in dental caries. Lactobacilli were also found to play a role in the progression of disease. However the underlying mechanism of immune response to caries is unclear. The association between secretory IgA (s.IgA) and cariogenic microorganisms is still controversial. The purpose of this study was to assess the level of salivary IgA in caries free children, and children with SECC and their corresponding mothers. The study also aims at correlating the children's levels to their mothers'. Sixty children and their mothers attending the dental clinic in King Abdulaziz University participated in our study. Their age ranged from 3 - 5 years. The study groups consisted of thirty children with SECC and a control group consisting of thirty caries free children. Children together with their mothers were examined and their caries level was recorded. Stimulated saliva was collected from each participant for immunological assessment. The secretory IgA (s. IgA) level was assessed by ELISA test. Our study has shown that children with SECC and their mothers had higher levels of s. IgA than the caries free children and their mothers. A positive high correlation was found between secretory IgA of mothers and children in both groups.