Abstract: A series of well defined polydimethylsiloxane-b-polydodecafluoroheptylmethacrylate diblockcopolymers (PDMS-b-PDFHMA) were prepared via RAFT polymerization using trithiocarbonate terminated polydimethylsiloxane as a macromolecular chain tranfer agent. The molecular weights and chemical structures of the fluorosilicone diblock copolymers were characterized by GPC, 1H-NMR and FT-IR. The effect of fluorine content on surface energy was also investigated by static contact angle measurement. Results show that dibockcopolymers have the controllable molecular weights and excellent surface properties.