A color cathode ray tube which has its resolution improved all over its screen covering the central portion and the peripheral portion, either by elongating or narrowing the plate length of plate electrodes (243), which are formed between a first kind of focusing electrode (241) and a second kind of focusing electrode (242) constituting together the electrostatic quadrupole lens of a halved focusing electrode (24) and which are connected with the second kind of focusing electrode (242) at the vertical portion (2430) of a passage for a central electron beam, or by making the shape of the central electron beam passing hole of an electrode (245) formed with the electron beam passing holes of the first kind of focusing electrode (241), longer than the shape of the beam passing holes for the side electron beams.