PURPOSE: To provide an electrode element supporting rod, which can make the heating condition of the body structure of electron guns of different types constant at the time of beading work and with which the visual discrimination of the body structure of electron gun is facilitated.

CONSTITUTION: Electrode element fixing surfaces of electrical insulating supporting rods 20, 21 for fixing each electrode element of the body structure of an electron gun, which has at least a cathode 10 and a first grid electrode 11-a fourth grid electrode 15, are colored with the same color independently of the type of the body structure of electron gun, and the appropriate color or a pattern is given to the beading support surface which is the surface. A heating condition by burner is thereby made constant to enable the discrimination of the body structure of electron gun after the assembly.