Mormyridae are important in Fisheries in Nigeria. Twenty six species are found in Nigerian waters and the largest of the species, Mormyrus rume, capable of growing up to 100 cm is common in the middle reaches of Cross River. Being common in the catches, heavy metal concentrations in its tissues were investigated in order to find out if the concentrations are above permissible levels for human consumption. Fish specimens were obtained from local fishers that fish with gill net, cast net as well as local traps. The gills, muscle, liver, heart and spleen were dissected out for analysis of metal concentrations. Metals analysed were lead, aluminium, zinc, iron, cadmium, chromium, cobalt and copper. Lead and aluminium were not detectable in any of the tissues. The highest mean concentrations of zinc was 0.042 ppm, iron was 0.12 ppm, chromium was 0.031 ppm, cobalt was 0.032 ppm, copper was 0.035 ppm and cadmium was 0.055 ppm. Statistical analysis showed variations in concentrations of metals in various tissues. All these were lower than maximum permissible levels in foods by World Health Organisation (WHO), Federal Environmental Protection Agency of Nigeria (FEPA) and United State Environmental Protection Agency (USEPA). Although this fish leads benthic lifestyle, where these metals are expected at higher concentrations, it was seen not to bio accumulate heavy metals to intolerant levels.