PURPOSE: To provide a color picture tube whose manufacturing yield is increased by raising the limit of external forces exerted on the bottom portion of a mask frame and causing deformation of the effective surface of a shadow mask mounted on the mask frame.

CONSTITUTION: In a color picture tube which has a built-in mask frame 1 having a shadow mask 7 partially welded at its mask skirt portion 9 to the welding area 4 of a mask-frame side wall 3, the mask frame 1 is curved at its end area 5 ahead of the welding area 4 of the side wall 3, in the inward direction of the side wall 3 and at least near said welded portion; during the manufacturing process of the color picture tube, the end area 5 is therefore prevented from pressing the inner surface of the mask skirt portion 9 with an external force exerted on the mask frame 1 and so does not cause deformation of a mask effective surface 8; therefore the manufacturing yield of the color picture tube is increased.