The present invention provides a method and device for observing a specimen in a field of view of an electron microscope. The method may include the steps of obtaining an image formed by irradiating an electron beam to a specimen; presetting an arbitrary search target pattern similar to a search target form; determining whether the field of view has a brightness inappropriate for observation or search; adjusting electro-optical conditions of an electron microscope when it is determined that a field of view is appropriate for observation or search; searching the field of view for a form having the same pattern as the search target pattern; and measuring a number of the forms obtained by the search.
