To provide a manufacturing method for a spherical valve member capable of solving such problems that a defect occurs in a valve member produced according to a conventional manufacturing method, in particular, a leakage and a stagnant flow occur due to a scratch on a surface thereof.

In this manufacturing method for the valve member two symmetrical semi-spherical valve members 11 in which their cross sections are formed into a shape of substantially 'square having two lines' therein due to the presence of a cylindrical part inside a semi-spherical part are formed by a thermal forging molding method. These two semi-spherical valve members 11 are joined by friction-welding to form one spherical valve member 1. A scratch on a surface of the spherical valve member 1 is eliminated by adopting the thermal forging molding method and friction-welding to make a flow smooth. Moreover, a weight of the spherical valve member 1 is reduced to prevent the wear of a stop cock and prolong its service life.