Hybrid semiconducting silver-tetracyanoquinodimethane (AgTCNQ) nanowires decorated with Ag nanoparticles have been synthesized at room temperature in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate. Hydroquinone was applied to reduce Ag þ and TCNQ to silver nanoparticles, and TCNQ À , respectively, under ambient conditions. AgTCNQ nanowires were formed via spontaneous electrolysis between Ag metal nanoparticles and TCNQ, and reaction between Ag þ and TCNQ À . Microscopic, spectroscopic, and X-ray characterizations all confirmed the formation of crystalline Ag nanoparticle-AgTCNQ nanowire hybrid structures. The ionic liquid was used as a reaction medium, but also as a stabilizing (or blocking) agent to control the nucleation and growth rate of AgTCNQ wires.