The distribution of magnetic field of the terrestrialmagnetism is complicated. Thus, it is difficult to compensate the deviation of the arrival point of the electron beam onto the fluorescent material plane due to the influence of external magnetic field such as the terrestrialmagnetic field, when only an inner magnetic shield and a mask are installed in a flat type color CRT to avoid such influence, in certain regions on the earth, where such CRT is used. The first countermeasure of the influence is using of a stripe type color cathode ray tube, which has a large allowance to the deviation of the arrival point of the electron beam in the vertical direction. Next countermeasure is disposing of a filler made from non-magnetic material or hard magnetic material and/or a gap between the inner magnetic shield and the frame of the mask so as to flow out the magnetic flux, which come from the edge of inner magnetic shield and tend to flow into the inside space of the mask.