Eleven isolates of identified six different pathotypes of Bipolaris sorokiniana were compared for their effect on leaf blight severity and yield contributing characters of wheat cv. Kanchan by inoculating plants at maximum tillering stage under control condition in pot trials. The pathotypes differed among themselves in respect of leaf blight severity that scored from 71 to 82. But the pathotypes did not differ among themselves regarding their effect on grain yield of wheat.