A new pathway for the synthesis of HPMA graft copolymers was developed and their self-assembly into hybrid hydrogels was investigated. Linear water-soluble polyHPMA was chosen as the polymer backbone, whereas coiled-coil forming peptides, covalently attached to the backbone, formed the grafts. Peptides of different chain lengths were chosen for evaluation. The results revealed that graft length greatly affected gelation ability. At least four heptads were needed to facilitate the hybrid system to form hydrogels under the experimental conditions used. The major factors affecting the kinetics of hydrogel self-assembly were concentration and temperature.