Root pathogens are important constraints to banana and plantain production worldwide. A survey was conducted in Cameroon between 1994 and 1995 to identify the major root pathogens of banana and plantains in large scale commercial plantations and in peasant plantations. Investigations were also carried out to determine the effects of the pathogens on plant growth characteristics. Several nematode species were isolated from banana and plantain roots. Radopholus similis, Helicotylenchus multicinctus, Pratylenchus goodeyi and Meloidogyne spp were the most important nematode species found. The burrowing nematode R, similis was the dominant species at lower elevation (below 500m asl). At higher elevation (above 1000m asl) the lesion nematode P. goodeyi was the most important.Cylindrocladium sp was the only pathogenic fungus isolated from banana root samples collected from commercial banana plantations. Root damage level in most of the plantations varied between moderate and severe. In pot studies, the nematode R, similis and the fungus Cylindrocladium significantly reduced plant growth parameters of tissue culture plantlets. Plants inoculated with either the nematode or the fungus showed less damage than those inoculated simultaneously with the nematode and the fungus. These findings indicate that root parasitism in commercial banana plantations in Cameroon is caused by a nematode-fungus complex.