The study of bioadhesion is significant to applications in a variety of scientific fields. Techniques that are surface-sensitive need to be utilized to examine these kinds of systems because bioadhesion occurs at the interface between two surfaces. Recently, sum frequency generation (SFG) has been applied to investigate different bioadhesive processes because of its intrinsic surface specificity, excellent sensitivity, and its ability to perform experiments in situ. SFG studies on the bioadhesion of fibrinogen, Factor XII, and mefp-3 on various surfaces will be discussed in this review.