Electron microscopy is the only imaging technique that allow direct visualization of viruses. During 1970 to 1980, EM contributed to the discovery of many types of viruses and served as important diagnostic tool for identifying viruses directly in biological samples, either in crude/purified preparation or in ultra-thin sections of infected tissues. Later with the advent of highly sensitive techniques, like enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR), EM became obsolete. However, application EM is still used in routine diagnosis to supplement the molecular assays. In electron microscopy, the most commonly used method is dip preparation followed by ISEM and decoration test for the characterization and identification of viruses. Immunogold labelling, is also used to see the location of antigens in different part of host tissue and decoration especially in viruses having envelopes like tospo and rhabdoviruses.