The invention relates to a manual sealed adjustable ball valve, which comprises a valve body, a ball body, a valve seat and a valve rod, wherein the valve rod drives the ball body to rotate, the valve seat can be glidingly arranged in a cavity of the valve body arranged in a communicating part of an inlet fluid passage and an outlet fluid passage relative to the valve body, a sealing ring capable of sealing and blocking a communicating part of the cavity of the valve body and an internal flow passage of the ball body is annularly arranged on the valve seat, a valve seat driving device used for driving the valve seat to integrally move to the ball body direction is arranged between the valve body and the valve seat, and the valve seat driving device comprises transmission components, and the axial lines of the transmission components are mutually crossed and matched. The manual sealed adjustable ball valve has the advantages that the worm wheel and worm rod type driving valve seat integrally moves in a direction towards the ball body, so a sealing ring and the ball body have a good sealing effect, and the problem of easy leakage caused by regulation through a plurality of regulating points in the prior art is avoided; the ball valve also has the characteristics that the continuous regulation is realized, and in addition, the regulation quantity is greater; in addition, the ball valve also has an overpressure discharging function, the problem of ball valve damage caused by higher pressure inside the cavity of the valve body is avoided, and the service life of the ball valve is prolonged.