Ball valve

The utility model relates to a ball valve. A valve seat of the ball valve is a rigid valve seat. Both sides of a supporting hole of an upper valve shaft of a valve core are provided with upper deformation ditches which have directions which are consistent to the direction of a hole of the valve core. Both sides of a supporting hole of a lower valve shaft of a valve core are provided with lower deformation ditches which penetrate the hole of the valve core and have directions which are consistent to the direction of the hole of the valve core. The lower end of the lower deformation ditch is extended for forming a deformation acting force ditch, the width of the deformation acting force ditch is identical to the short shaft diameter of an elliptical shaft table on the lower valve shaft, and the height of the deformation acting force ditch is identical to the height of the elliptical shaft table. When the valve core rotates to a closing position, the valve core and the valve seat are mutually impacted and sealed because of the spread of the lower deformation ditch and the fold of the upper deformation ditch. The utility model has the advantages of abrasion resistance, high temperature resistance, aging resistance, long service life and better tightness.