The authors recently experienced a case of dysgeusia on bilateral anterior two third of tongue, caused by after tonsillectomy. A 52 year old male patient had been taken tonsillectomy under local anesthesia on July 18th, 1980 at local clinic and he visited our hospital on Aug. 12th, 1980 because of loss of sweet, sour and salt sensation. Local finding of tonsillectomy wound was not specific, but partial loss of general sansation and dysgeusia on bilateral anterior two third of the tongue were found. Result of Pinkin's 3-drop forced choice method of chemical taste evaluation was total loss of taste on left side and partial loss of taste of right side. Response of urea for bitter in this method was positive on bilateral posterior one third of the tongue.