Abstract: The fungistasis of tebuconazole to Rhizoctonia cerealis causing wheat eye spot were studied. The result showed that tebuconazole has the highest activity against this pathogen with its average EC500.048 9 μg/mL. The morphology of mycelia and pathogenicity of R. cerealis changed obviously after tebuconazole treatment. Tebuconazole inhibited mycelia growth and led distinctly electrolyte leakage, but it did not inhibit sclerotium germination.