Severe viral-like symptoms were observed on potato plants growing in Assiut governorate (Upper Egypt) during 2010, 2011 and 2012 growing seasons. Typical viral-like particles were observed under Electron microscopy exanimation. These parti- cles were either rod shape about 750 nm in length or bacilliform about 130 nm in length, and resemble Potato virusY (PVY) and Alfalfa mosaic virus (AMV) particles, respectively. Several biological, serological and molecular methods were applied to identify these particles. Serological tests proved that the causal viruses responsible for these symptoms were AMV and PVY. RNA extracted from infected potato as well as healthy potato plants was tested in Reverse Transcription Polymerase Chain Reaction (RT-PCR) using specific primers to amplifycoat protein gene of AMV or PYV. RT-PCR results proved that the symptomatic potato plants are being infected with AMV or PVY, either separately or simultaneously (mixed infection). To the best of our knowledge, this is the first molecular identification of AMV and PVY infecting potato in Assiut governorate, Upper Egypt.