Quercus liaotungensis is a deciduous broad-leaved oak tree and dominant species in the forests of Loess plateau in China. Q. liaotungensis forests play important ecological function of soil and water conservation in the Loess Plateau. Oaks are critically dependent on Ectomycorrhizal (ECM) fungi for their establishment and growth. However, there are few reports about ECM community on Q. liaotungensis forest in this area. To clarify the changes in ECM community structure on Q. liaotungensis forests along slopes were examined. Fine roots of Q. liaotungensis were collected from different slope position (the upper, middle and lower part of slope) on Q. liaotungensis forests of Mt. Gonglu in Yan’an of China. Collected roots were sorted by morphotype, and proportional colonization of each type was determined. DNA was subsequently extracted from individual root tips for PCR-RFLP (polymerase chain reaction, restriction fragment length polymorphism), and rDNA sequencing of the ITS1/5.8S/ITS2 region was carried out to identify fungal morphotypes. More than one hundred of fungal species were found in the study site. The structure of ECM fungal communities shifted from the upper part to the lower part of slope, which may be interpreted by the difference in abiotic and biotic environments.