Self-assembled monolayers of 8-; 5-; and 2-hydroxyquinolines (8-; 5- & 2-hqs) are obtained for the first time at the electrified Au(111)1100 mM HClO4 interface via electrochemical scanning tunneling microscopy (EC-STM). We observed that 8- and 2-hqs form stripe patterns, both on the negatively charged reconstructed Au(111)(p x root 3) as well as on unreconstructed Au(111)-(1 x 1) surfaces. The adlayers are composed of dimer rows stabilized by both cyclic O-H center dot center dot center dot N hydrogen bonds and van der Waal interaction between the neighboring molecules. The O-H center dot center dot center dot N bond is made between the 8 and 2 position -OH acting as hydrogen bond donor and N in the pyridine ring as the hydrogen bond acceptor. When the 8 and 2 position of hydroxyl group in the pyridine ring is replaced to the 5 position in the benzene ring, we observed a monolayer with grid-like structure (trimeric pattern) that are qualitatively different from those of 8- and 2-hqs. Dimer formation is completely broken in the case of 5-hq, in which C-H center dot center dot center dot O and C-H center dot center dot center dot N hydrogen bonds play a key role in company with coadsorption of solvent molecules or electrolyte ions to support the stability of the adlayer. However, the H-bond networks of these adlayers are destabilized at the positive charge densities of Au(111). While 2-hq molecules form disordered chemisorbed adlayer, 8- and 5-hqs are subjected to electrochemical oxidation.