PURPOSE: To improve adhesion of the subject fiber to matrix resins without impairing operating efficiency in yarn twisting steps, etc., by applying a specific oiling agent to the surface thereof in which a solid cation exchangeable inorganic compound is adhered.

CONSTITUTION: Wholly aromatic polyamide fiber obtained by applying an oiling agent having ≤100cSt viscosity at 50°C to the surface thereof in which a solid cation exchangeable inorganic compound is adhered. The above-mentioned oiling agent contains a polyether-based copolymer which is a random or block copolymer of propylene oxide and ethylene oxide having a nitrogen atom- containing compound at the terminals [copolymerization molar ratio of the propylene oxide to the ethylene oxide is (70/30)-(0/100) and the average molecular weight thereof is 400-800].