To produce an inorganic functional agent-containing polyester fiber that has excellent functions, such as deodorizing and antimicrobial properties, and also excellent thermal resistance and dyeability, and is suitable for applications to clothing.

This inorganic functional agent-containing polyester fiber, which is preferably used for sheaths of composite fibers of core and sheath type, comprises (A) 40-95wt.% of polyester whose main repeating unit is ethylene terephthalate, and (B) 5-60wt.% of polyester whose main repeating unit is esters composed of 4-7C glycols and terephthalic acid as well as well as inorganic functional agents. This polyester fiber is produced by compounding a master batch composed of the polyester (B), as the base polymer, and inorganic functional agents with the polyester (A).