Abstract: In a method of and an apparatus for handling a charged particle beam, at least one of a signal representative of the astigmatism and a signal for correction of the astigmatism is obtained by computation on the basis of values detected under a certain condition from signal particles derived from an object which is moved repeatedly at least two directions with respect to a charged particle beam. The amount and direction of astigmatism thus computed are displayed respectively for manual correction. Astigmatism correction and focusing can be also carried out automatically.