The synthesis of novel diblock copolymers consisting of a semifluorinated block of poly(1H,1H,2H,2H-perfluorooctyl methacrylate) (PFOMA) and a hydrocarbon block of polycaprolactone (PFOMA-b-PCL) was achieved by the combination of enzymatic ring-opening polymerization (eROP) and atom transfer radical polymerization (ATRP). The chemoenzymatic synthesis of diblock copolymers from a bifunctional initiator in two consecutive steps was investigated. A polycaprolactone (PCL) macroinitiator was obtained via enzymatic ring-opening polymerization initiated by the bifunctional initiator. A PFOMA block was then grown from this PCL macroinitiator. In addition, block copolymers were successfully prepared by a two-step-one-pot synthesis using a sequential monomer addition technique.