The main objective of the present work was to study the influence of yeast-derived mannoproteins on the adherence to and invasion of Caco-2 cells by Campylobacter jejuni. Mannoprotein fractions were prepared by enzymatic and thermal extraction methods. The method used to prepare the mannoprotein extracts influenced their composition and determined the efficacy of the extract against C. jejuni adherence and/or invasion. The availability of mannose in the mannoprotein fraction seemed to be important for inhibiting effective adherence and invasion of Caco-2-cells by C. jejuni, although protein moieties also played a role in the process. The study of the mechanisms involved in the inhibition of C. jejuni adherence and invasion by mannoproteins may have further implications in the control of this foodborne pathogen.