In this study, a new miscible rod–rod polypeptide blend system comprising polytyrosine (PTyr) and poly(γ-methyl L-glutamate) (PMLG) was developed. Differential scanning calorimetry revealed significant positive deviations in the glass transition temperatures of these PTyr/PMLG blends, arising from intermolecular hydrogen bonding between the phenolic OH groups of PTyr and the side chain CO groups of PMLG, as well as secondary structural changes of the polypeptides confirmed using solid state nuclear magnetic resonance spectroscopy.