The invention discloses an underground throttler, which is applied in the technical field of gas extracting in an oil and gas field. A fishing head is sheathed on the outer wall of a sliding sleeve; a slips is suspended at the lower end of the fishing head; a slips cone is in threaded connection with the outer wall of the lower end of the sliding sleeve; an upper gas nozzle pipe is fixed in the sliding sleeve through a pin; the slips cone is provided with a central hole which is provided with a lower gas nozzle pipe; the lower end of the lower gas nozzle pipe is provided with a spring; the lower end of the spring is provided with a circular spring seat; a gas nozzle is embedded at the lower part of the stepped central hole of the lower gas nozzle pipe; a seal rubber cylinder is fixed at the lower end of the slips cone; a rubber cylinder cone is arranged at the lower part of the seal rubber cylinder; a protection cover is connected with the lower end of the rubber cylinder cone; and a filter mask is in threaded connection with the lower end of the lower gas nozzle pipe. The underground throttler of the invention has the beneficial effects of adopting the seal rubber cylinder and the rubber cylinder cone to lead the seat sealing to be more reliable, adjusting the position of a seal ring, adopting a spline structure and a knob unloading ring to reduce the damage of the seal ring and prolong the service life of the seal ring, and reducing the damage of the produced sand to the trottler.