The studies were carried out to diagnose of disease chickens that were raised at the chicken farms located in Chung -nam province and evaluated potential of mold growth inhibition of antifungal agent, Mold-X. The diseased 25 chickens that were shown clinical sign such as anorexia, respiratory symptoms, were suspected aspergillosis. The results obtained were summarized as follows ; 1. The diseased thickens were diagnosed aspergillosis according to clinical sign, pathological finding, isolation of etiological agent. 2. The growth of mold was conciderable inhibited by the Mold-X of 300 ppm level.