A pressure balance type flip plug valve, consisting of a valve body, a cock, a stem and a filler, the cock is a conical valve plug over the upper end of the upper end, the cock is located in the inner cavity of the valve body, the stem driving cock rotates, the sealing surface of the cock is a cone, the stem and the cock are connected through the cross connector, and a cylinder between the stem and the cock is equipped with a cylinder. Spring or butterfly spring, the lower end of the valve body is fixed with a valve cover, the valve cover has a adjusting shaft, the lower end of the adjusting shaft is worn out of the valve cover and the top top cock, the lower end of the cock has a first check valve, the seal face of the cock is equipped with a seal oil tank, the valve body has a tank, the oil tank of the valve body is connected with the seal oil tank of the cock. The valve body is provided with an oil injection valve that is connected with the oil storage tank. The pressure balance type flip plug valve can be used under high temperature, high pressure and harsh conditions. It has the advantages of reliable sealing, small operating torque and long service life.