Oxidized PAN (OXI-PAN) fibers were used for the precursors of activated carbon fiber in study. How drying temper-ature affected the properties of carbon fibers on activating process of carbon fibers was investigated. The specific sur-face areas of activated carbon fibers have been determined on a series of chemicaly activated carbons with KOH andNaOH. The experimental data showed variations in specific surface area, iodine and silver adsorptions by the activatedods. This was because the ionic radius of iodine was smaller than the interior micropore size of activated carbon fibers.Silver adsorbed well in NaOH activated carbon fibers rather than KOH activated carbon fibers in this study.