Prion diseases are a group of neurodegenerative conditions affecting both humans and animals. Among the methods used in prion disease diagnosis, immunoenzymatic tests as well as immunohistochemic and fluorescence analisis are distinguished. Currently, aptamers, which are single-stranded RNA or DNA oligonucleotides, are implemented with the above-mentioned methods. They play the role of artificial ligands that may be applied instead of widely used antibodies.