Human saliva was chromatographed on Sepharose CL-2B and was found to separate into two peaks. The first peak contained nonspecific agglutinin(s) as the agglutinin gave similar titers with all Streptococcus mutans serotypes. No protein or α- and γ-chain or secretory piece activity was found in association with this agglutinin. Components of the second peak demonstrated protein, α- and γ-chain and secretory piece activity as evidenced by precipitation lines in gel diffusion using the appropriate monospecific antisera. The agglutinin contained in this peak when derived from different individuals showed varying titers against different serotypes of S. mutans. The second peak was also chromatographed on Sephadex G-200. A specific agglutinin was then found in the void volume peak which demonstrated α-chain and secretory piece activity as shown by gel diffusion studies. The results from this work would appear to demonstrate a nonspecific agglutinin and a specific agglutinin which has all the properties of S