As a part of our ongoing investigations of alpine plants from the Valley of Aoste (Italy), the methanol and dichloromethane extracts of 45 plants have been studied from a phytochemical view point. These species grow at altitudes from 2200 to 2700 meters in extreme habitat. Thus, 100 extracts were investigated for their free radical scavenging activity against DPPH and antifungal activities with different tests: against the plant pathogenic fungus Cladosporium cucumerinum by direct bioautography, the commensal yeast Candida albicans by bioautography « agar overlay » and Pyrenophora teres by mycelial growth tests in artificial media. Some extracts showed significant activities and were studied by measuring the inhibition of the fractions against the growth of the pathogenic fungi. About twenty compounds have been isolated and the structures of these compounds were determined by means of spectrometric methods, including 1D and 2D NMR experiments and MS analysis.