1-Fluoro- and 1,3-difluoroazulenes were synthesized by the reaction of azulene with N-fluoropyridinium salts in acetonitrile. Methyl azulene-1-carboxylates were also fluorinated to give the corresponding 3-fluoro derivatives. On the basis of the UV-visible absorption spectra, the fluorine atom acts as an electron-donating group to the azulene π-system due to the +Iπ effect.