A new species of a cephalogonimid digenean trematode Cephalogonimus fasciatusii is described from a freshwater teleost Trichogaster fasciatus Bloch & Schn. from a sub-shivalik lake Mansar, Jammu. India. The worm has an aspinose ovate body, with an anterior testis consistently smaller than its posterior testis, vitellaria extending over the whole of oro-testicular zone, caeca extending into posttesticular zone and non-operculate eggs. A key to the only 3 species of the genus Cephalogonimus known so far from fishes is also given.