A fiber which has an excellent effect of inhibiting virus multiplication or eradication (deactivation); a process for producing the fiber; and a textile product comprising the fiber are provided. The method for producing an antiviral fiber comprises bonding a metal ion of a metal having deactivation effect to a virus and poor solubility in water to at least a part of a carboxyl group of the fiber having a cross-linked structure and having a carboxyl group in a molecule of the fiber; and then depositing fine particles of the metal and/or metal compound in the fiber by reduction and/or substitution reaction.