Abstract: Protein structure modeling is a basic and important problem in bioinformatics. According to the chain-character of protein structure, based on the Cα atoms, and applying the theory of B-spline space curve, a novel bioinformatics model named BSSC (B-Spline Structure Curve) is derived for the protein backbone structure. BSSC model has the characteristics of continuity, controllability and expansibility, which are readily used to investigate various bioinformatics problems on protein structure.