A cathode ray tube is provided. The cathode ray tube according to the present invention includes a panel having a fluorescent film formed on the inner surface thereof, a shadow mask frame assembly disposed inside the panel, a funnel to which the panel is sealed and having an electron gun installed in a neck portion thereof and a deflection yoke installed around a cone portion thereof, and a magnetic field shielding portion which is installed along the wall of the funnel and includes a metal plate for blocking the influences of terrestrial magnetic fields. In the cathode ray tube according to the present invention, it is possible to block the influences of terrestrial magnetic fields with a magnetic field shielding portion having a simple structure.