A novel hollow phenolic fiber was successfully prepared by the dissolution of the uncrosslinked core of the partially crosslinking spun filament derived from the melt spinning of the phenolic resin. A series of hollow phenolic fibers with various degrees of hollowness were obtained through different preparation processes. The hollow phenolic fibers were characterized with scanning electron microscopy, infrared spectrometry, and thermogravimetric analysis. The formation of the hollow core in the hollow phenolic fibers was attributed to partial crosslinking of the filaments during the curing process; the prepared hollow phenolic fibers had high crosslinkage after the second cure, their thermal stability was as excellent as that of the solid phenolic fiber, and their hollowness could be regulated from 5 to 85%. (c) 2007 Wiley Periodicals, Inc.