To provide a tool holder providing a holder body with a filtering section capable of maintaining a filtering function without removing a filter in the case of providing a fine mesh filter near a cutting edge of a tool to prevent the quality degradation of a machined surface.

This tool holder comprises a cutting fluid supply passage A for feeding a cutting fluid supplied from a tank to a holder body 4 mountable to a cutting tool 1 with a cutting fluid supply hole bored, into the cutting fluid supply hole of the tool; the filter 5 provided in a replaceable manner at an intermediate part of the passage; a spool 7 for changing the supply passage A of the supplied cutting fluid over to an inflow side passage B to the filter 5 or over to an outflow side passage C; a tool direction discharge passage D connected to the inflow side passage B and opened to the outside of the holder body 4; a positioning rod 9 with a cover detachably mounted to the discharge passage to position the spool 7 to the outflow side passage C when closing the discharge passage; a stop part for positioning the spool 7 to the outflow side passage C; and a spring 8 for force-fitting the spool 7 to the stop part.