The present invention provides a new drill chuck that resolves the problem that the excessive clamping force of the existing drill chuck makes it inconvenient to open the drill chuck and easily damages the cutters. The new drill chuck comprises a front-body, an after-body, and clamping jaws, wherein a thread is provided on the clamping jaw, the after-body is provided with master gears, slave gears are provided between the clamping jaws and the after-body, the master gear fits with the slave gear, a thread is provided inside the slave gear, and the thread of the slave gear fits with the thread of the clamping jaw.