Perfluororosilanes1 are highly stable compound, which used in a wide range of applications to heat resistance, impermeable to chemicals, sliding properties, electric characteristics and it has been also exhibit special repellency to water. [2][3][4][5][6][7] In addition, the measurement of wetting property and hydrophobic coating by the use of perfluorosilane film on metal oxide surface are widly studied.1 And as a related subject, dendrimers are well defined macromolecule composed a focal point, it has unified and applicable nummerous end groups.8 This report presents the preparation of carbosilane dendrimers having peripheral groups replaced by fluorinated functions as a characteristic peripheral branches. These dendrimers expects that show a new characteristic presisonal properties as a hydrophobic matter. Fluorinated alkyl branches having F 3 C(CF 2 ) 7 (CH 2 ) 2 O-(Heptadecafluoro-1,1,2,2-tetrahydro-1-decanoxy; HDFD) and F 3 C(CF 2 ) 5 (CH 2 ) 2 O-(Tridecafluoro-1,1,2,2-tetrahydro-1-octanoxy (TDFO) functions were used.The carbosilane dendrimers that was began cyclic siloxane core and developed to high generation with Si-O-C branches on the periphery were published as previous reports.8,9 These dendrimers were prepared by divergent synthetic methods using hydrosilation of vinyl rest on siloxane core ((MeSi-(CH=CH 2 )O) 4 ; 1, 3,5,7-tetramethyl-1,3,5,7-tetravinyl-2,4,6,8-tetraoxacyclooctane) with methyldichlorosilanes (MeSiHCl 2 ). The resulting compound 1G[4,2]-8Cl with eight Si-Cl bonds on the periphery yields nearly quantitative, determined by NMR. The reaction followed by the addition of fluorinated alcohol The procedures, hydrosilation and addition of fluorinated functions on the dendritic periphery have been well controlled by NMR spectroscopic determination. The observation of disappearance of vinyl signals between 5.1-5.3 ppm and appearance of characteristic methylsiloxane signal by hydrosilation process near 0.0-0.3 ppm was clearly determined. The fluorinated dendrimers nG[4]-8nOC 10 H 4 F 17 , and nG[4]-8nOC 8 H 4 F 13 was purified by column chromatography which can be removed dendrimers with hydrolyzed branches, free fluorinated alcohol and solvated salts in reaction medium. The yields of the prepared dendrimers have been obtained almost quantitatively in hydrosilation procedure and alcoholysis in general very high but some lower yield than hysrosilation procedure because the chromatographic purification methods brought reduced the yields. The spectroscopic measurement of reaction medium showed almost quantitatively which means the both reactions were well progressed. The analyses of MALDI mass spectra and elemental analysis made it possible to obtain the purity and unified properties. The MALDI mass analysis of the fluorinated dendrimers were not observed the molecular peaks. Scheme 1. Preparative methods of perfluorosilane dendrimers.