The fish Plectorhinchus cinctus Lacepede, 1801 is infected with a number of helminth parasites causing tissue damage to various organs. In the present study histological changes caused by Proctoeces maculatus (Looss, 1901) to the stomach tissue of the fish is reported. The fish were caught from Karachi coast, Pakistan. The infected tissue from the stomach was passed through graded ethanol, cleared in xylene, impregnated and embedded in Paraffin wax by using a microtome. Tissues were stained with Haematoxylin and eosin for light microscopy examination. The sections showed atrophic gastritis in the mucosa and several empty spaces were seen in the underlying layers, similarly the architecture of villi was completely destroyed.
