In an electron microscope correction of spherical and chromatic aberration can be achieved in a number of freely adjustable directions by using a multipole correction element whereby a magnetic or electrostatic octupole field, rotatable about the optical axis, or a combined rotatable magnetic and electrostatic quadrupole field is generated. A corrected overall image can be obtained by combination of images successively corrected in different directions. In the case of holographic images, correction in the direction perpendicular to the line direction in the hologram enhances the accuracy of phase determination. A correction element of this kind, having comparatively small dimensions of from 1 to 2 cm, can be simply mounted, notably in a transmission electron microscope, in a space provided for the stigmator.