Fungi play an important role in the soil ecosystem, it decompose nutrients and elements to simple compounds for plants growth, also play a rolein biological control for suppression of plant pathogens. Isolation, purification of soil fungi using conventional microbiological techniques is hard but it needed for study the distribution of fungal community in soil rhizosphere. Molecular techniques using 18s rDNA based sequences analysis provide the taxonomic resolution for identification of fungal species and strains, also provide information on the diversity and dynamics of fungus in environmental samples. In the present study, isolation and purification of fungi near some medicinal plants soil rhizospher from Saudi Arabia regions, extraction of DNA from isolated fungal strains, 18S-ribosomal-DNA using universal primer sequences were used for amplification of 18S rDNA gene from each isolated fungus. Clear banding patterns were obtained with each isolated fungi by using primer sets. Sequencing of isolated 18S-ribosomal-DNA done by Macrogen Company in Korea and compared to known rDNA sequences using NCBI taxonomy were also done. Phylogenetic tree construction of each isolated fungus obtained and results confirmed that the 18S-rDNA PCR amplification are reproducible and confirming the fingerprints which indicate differences of the fungal community in used soil rhizosphere.