Proteins are promising materials for biomedical and renewable polymers applications. One important property is the stability of the protein in the presence of degrading enzymes during bioresorption or biodegradation. In this study, we degraded proteins corn zein, egg albumin, feather keratin, lactalbumin, and wheat gluten under simulated composting conditions. The proteins had different molecular weights, polarity, secondary structures, and varying amounts of inter-molecular cystine bonding. From the biodegradation behavior as a function of time, four key behavioral features of the biodegradation were found: t_lag(lag time), t_stop(time at which biodegradation stopped), D_i (initial biodegradation rate), and D_ss(steady-state biodegradation rate). It was observed that D_ss and t_stop depended strongly on cystine bonding, polarity, and α-helix content of the protein. Cystine bonding stabilizes the structure against enzymatic attack. More polar proteins allow enzymes to be transported in by water and provide sites for the enzymes to anchor. α-helices are compact structures where the C- and N-terminal regions of the peptide bond are shielded by the amino acid side groups, thus inhibiting enzymatic attack. Understanding of these features allows for the synthesis and formulation of protein-based materials with controlled bioresorptions or biodegradations based on the type of molecular structure built into the material.