Onychomvcosis , a fungal nail infection, has become one of the most important dermatophytoses. The current laboratory methods for diagnosis are the potassium hydroxide (KOH) scraping technique and fungal culture. Unfortunately, a predictably successful diagnostic approach to onychomvcosis does not yet exist, The purpose of this study was to develop a deoxyribonucleic acid (DNA)-based diagnostic method to improve the sensitivity and specificity of the detection and differentition of the pathogenic fungi of onychomycosis. This study attempted to detect fungi in the nail using Polymerase Chain Reaction (PCR) primer system that were designed in conserved sequences of the snuill ribosomal submit 18S-rRNA genes shared by most fungi and differentiated between species bv DNA sequencing technique of the amplified product. Material from 50 nails suspected as having onychoniycosts and 10 healthv nails as control were subjected in parallel to the three mycologtcal methods of detection; microscopic examination, culture, and PCR. Fragments of the gene coding for 18S-rRNA were amplified successfully from the suspected nails and DNA sequencing technique was sufficiently successfull to allow the recognition of individual species. The combined PCR-DNA sequencing technique appears to be a more sensitive detection and identification technique for onychoniycosis than conventional methods and has considerable diagnostic value.