Disclosed is a color cathode ray tube which can effectively improve impact resistance by setting a ratio of a curvature coefficient (a/b) of the shadow mask for a long axis to be in a range of about 100,000–135,000, and by setting a ratio of a curvature coefficient (c/d) of the shadow mask for a short axis to be in a range of about 60,000–360,000. Also, in defining ratios between a curvature radius of a center portion of the shadow mask and curvature radiuses along a horizontal direction, a vertical direction, and a diagonal direction, the curvature radius decreases towards the peripheral portions of the shadow mask, thereby improving impact resistance and drop characteristics and thus effectively preventing color purity from being degraded.