The precision synthesis and self-assembly of amphiphilic copolypeptides containing a recombinant elastin-like polypeptide (ELP) block used as a macroinitiator for the ring opening polymerization (ROP) of γ-benzyl-L-glutamate (γ-BLG NCA) are herein presented. The molecular weight of the resulting PBLG-b-ELP block copolypeptides was precisely controlled without the use of complex initiator or demanding experimental setup. Diblock copolypeptides were obtained with an excellent control of the polymerization highlighted by the dispersity below 1.04. These amphiphilic hybrid synthetic/recombinant copolypeptides were self-assembled in water and the nanoparticles obtained were characterized by a combination of dynamic light scattering and electron microscopy. A variety of morphologies, namely polymersomes, inter-connected worm-like micelles and spherical micelles, were evidenced depending on the hydrophilic ratio of the diblocks as well as the self-assembly procedure.