We have fabricated silica nanochannels with inner diameter as small as 20 nm using a scanned coaxial electrospinning and demonstrated their application for single molecule detection. A coaxial jet, with the use of motor oil as the core and silica sol-gel solution as the shell, is extruded through a coaxial source and deposited on the rotating collector as oriented nanofibers. They are then annealed to cross-link silica and eliminate motor oil, thereby forming nanochannels. Subsequently, a fluorescent dye was injected into the individual nanochannels via a capillary force and single molecule detection was performed by monitoring the photon signals from 5-Iodoacetamidofluorescein.