PURPOSE: To achieve operation of a reversible impact-operated boring tool in a reverse direction by terminating supply of control fluid being secondary pressurized fluid, without terminating supply of primary pressurized fluid which enables reciprocation of the reversible impact-operated boring tool.

CONSTITUTION: A reversible impact-operated boring tool 10 possesses a control fluid supply conduit 30 for supplying secondary pressurized fluid to a control sleeve, i.e., a direction control valve member 100 within the tool 10. By operating a lever 30 of a control valve 32, the control fluid supply conduit is controlled, and when the secondary pressurized fluid is supplied to the directional valve member 100, the reversible impact-operated boring tool is operated in the forward direction. On the other hand, when the supply of the secondary pressurized fluid to the directional valve member is terminated and the secondary pressurized fluid within the directional control valve member is exhausted via an opening 34, the reversible impact-operated boring tool is operated in the reverse mode.