The invention discloses a timpani pedal locking mechanism which comprises a foot pedal, a switch device and an arc-shaped rack, wherein the switch device comprises a touch rod and a tooth block; the touch rod is hinged to one side of the foot pedal; a pressure spring is arranged between the front end of the touch rod and the foot pedal; the tooth block is fixedly connected with one side of the touch rod and is clamped in a tooth seam of the arc-shaped rack under the effect of the pressure spring; the arc-shaped rack is longitudinally and fixedly connected onto a base of a timpani; the touch rod overcomes the action force of the pressure to swing and drives the tooth block to be disengaged from the arc-shaped rack; then, the tightness of timpani skin is regulated by pedaling the foot pedal; after a proper position is reached, the touch rod and the tooth block are reset under the effect of the pressure spring; and the tooth block can be correspondingly clamped and connected in the toothseam of the arc-shaped rack so as to lock the foot pedal. The timpani pedal locking mechanism has the advantages that the design is reasonable; the structure is simple; the use is convenient; and thelocking function can be realized.