Colletotrichum coccodes (Wallr.) Hughes has been recognized as one of casual agents of anthracnose roots pepper in south-eastern Poland. During 2007–2012 the species was isolated from roots of sweet pepper (Capsicum annuum L.) cultivated in the field. The purpose of the study was morphological characterization and biotic activity of C. coccodes isolates. Five randomly chosen isolates from fungus population and one reference isolate obtained from Bank of Plant Pathogens and Investigation of their Biodiversity of IPP-NRI in Poznan in Poland were studied. The character of culture like growth rate, the colour of averse and reverse and the formation of morphological structures of the fungus such as acervuli, conidia, sclerotia were studied. Ultrastructural observations of morphological structures were made using light and scanning electron microscopy. Biotic activity of C. coccodes was conducted using the method of biotic series on PDA. Seven species of test fungi were used in the study: Alternaria alternata, Aureobasidium pullulans, Gibberella avenacea, G. intricans, Fusarium oxysporum, Penicillium aurantiogriseum, Trichoderma harzianum. The biotic activity test showed that C. coccodes is a weak competitor, and its development in the rhizosphere of sweet pepper may be limited by numerous antagonists.