In order to establish the presence and distribution of Plesiomonas shigelloides in the Port Harcourt area, samples from different origins were examined. Standard microbiological methods were adopted for the analysis. The results showed a relatively high incidence in soil and water which are speculated to be reservoirs of the organism. A low incidence rate occurred in seafoods and humans. No P. shigelloides was detected from cattle and poultry. Although the isolation in humans was low 2.0% (8 of 400), five samples yielded P. shigelloides as the only enteropathogen. Four of the five were from diarrheic fecal samples, thus indicating the involvement of P. shigelloides in diarrhea.