The relationship of Venturia nashicola, the scab fungus of Japanese and Chinese pears, to the European pear scab fungus, V. pirina, was reexamined. Ascospores of V. pirina were longer and wider than those of V. nashicola and the conidia of V. nashicola significantly shorter than those of V. pirina. Results from mating experiments in culture clearly showed sexual isolation between the species. V. nashicola was only pathogenic on Japanese and Chinese pears and V. pirina was only pathogenic on European pear. It is concluded that V. nashicola is distinct from V. pirina.