From April to October, 2007, in 9 points of Ji stream and Inghwadal stream originated from Mt. Chilgap of the Mt. Chilgap Provincial Park area in Cheongyang-gun, habitat conditions, ichthyofauna, and dominant and rare species were investigated. 1. It was found that the ichthyofauna includes total 7 families and 27 species. Among them, the endemic species in Korea were 11 species such as Rhodeus uyekii, Microphysogobio yaluensis, Iksookimia koreensis, Pseudobagrus koreanus, Liobagrus mediadiposalis and others. it was about 40.7% of total fish, so showed relatively high peculiarity. 2. By sites, 17 species in the Station 4, 16 species in the Station 6, and 12 species in the Station 7 were observed, and the Stations 1 and 5 belonging to entering zone, were simple. 3. In the Station 8, the entrance of Cheonjang reservoir, Abbottina springeri was observed in isolated state, and in downstream region of Inghwadal stream, a foreign spcies, Lepomis macrochirus was observed. 4. Comparing ichthyofauna between Ji stream and Inhwadal stream water body, it was found that 23 species in the Ji stream water body and 13 species in the Inghwadal stream water body were observed, so it was identified that larger number of species inhabited in the Ji stream water body. 5. The dominant species were observed in order of Zacco platypus, Rhynchocypris oxycephalus, Acheilognathus koreensis, and Acheilognathus lanceolatus. 6. In case of the Chilgap reservoir and Cheonjang reservoir, there is a worry about illegal introduction of foreign species, so it is necessary to control its population stabilization by developing measures through continuous actual state survey in order to keep clear and stable ecological conditions.