In a color cathode-ray tube of the plural-beam type wherein the beams originate on a horizontal or vertical straight line and are directed into fields produced by a horizontal-vertical electromagnetic deflection yoke at predetermined incident angles to each other so as to converge at a color screen, magnetic shielding means, for example, secured to electron beam convergence plates, are disposed for selectively shielding at least one of the beams from the leakage flux produced by the horizontal-vertical electromagnetic deflection yoke in deflecting the beams in the direction of the line of origination thereof, whereby such leakage flux acts selectively on only the unshielded beam or beams for correcting a deviation between the positions of rasters on the color screen produced by the plural beams.