The water complexes of 4-fluorophenylacetylene and 2-fluorophenylacetylene were investigated using IR-UV double resonance spectroscopy. Both 4-lluoro-and 2-lluorophenylacetylenes form a cyclic complex with water incorporating C-H⋯0 and O-H⋯φ hydrogen bonds. These structures are similar to the phenylacetylene-water complex, implying that the fluorine substitution on phenylacetylene does not alter the intermolecular structure. Further, the presence of fluorine enhances the interaction of water with the acetylenic π electron density. This behavior of fluorophenylacetylenes is dramatically different from that of fluorobenzene and fluorostyrene. A second water complex was also observed in the case of 2-fluorophenylacetylene in which water interacts with fluorine atom and acetylenic C-C triple bond in a double-donor fashion. Additionally, two distinct 2-fluorophenylacetylene-(water)2 complexes were also observed. The first is a cyclic complex in which two water molecules bridge the hydrogen bond donor and acceptor sites present in 2-fluorophenylacetylene. The second is a kinetically trapped higher energy structure in which one water molecule acts as a double-acceptor. © 2009 American Chemical Society.