A color cathode ray tube includes an electron gun having an electron beam generating portion arrayed in a horizontal direction for generating three electron beams, and a main lens for focusing the three electron beams upon a fluorescent face, and a deflection yoke for scanning the three electron beams. The main lens has electrodes with three electron beams passages including a central electron beam passage and side electron beam passages. The main lens includes an accelerating electrode supplied with an accelerating voltage, a first focusing electrode supplied with a first focusing voltage, and a second focusing electrode supplied with a second focusing voltage. An axially asymmetric electron lens is formed between the first focusing electrode and the second focusing electrode.