Activated carbon fiber is known to posses better properties compared to granular and powdered variants, with significantly higher surface area and higher pore volume. Source of raw material and activation step are two crucial parameters for the pore development of activated carbon. Palm oil empty fruit bunch fiber contains naturally formed long open channels which offer better access of adsorbates into micropores. Chemical activation step typically involves inorganic acids such as phosphoric acid and sulfuric acid. However, such residues of inorganic acids might create unfavourable conditions for certain adsorption applications, if not removed properly from synthesized activated carbon fiber. Additionally, subsequent to the acid cleaning or removal step, most inorganic acids would eventually cause problems to the environment if acid disposal is not properly managed. This paper investigates on the effect of utilization of organic acids acetic acid and citric acid, as compared to commonly used inorganic acids, on the pore characteristics of palm oil empty fruit bunch fiber derived activated carbon fiber.