We evaluated the changes in taste responsiveness of anorexia nervosa (AN) patients during behavior therapy. Taste responsiveness of AN patients was lower at admission when compared to controls but it improved significantly over the course of treatment (p < 0.01). Taste responsiveness improved prior to increase in body weight. No significant correlation was noted between weight gain and improvement in taste responsiveness. The period required to reach a food intake of 1600 Kcal/day and the duration of hospitalization were highly correlated (r = 0.72, p < 0.05). Those who reached 1600 Kcal/day earlier showed more rapid improvements in taste responsiveness. These results suggest that decreased taste responsiveness in AN patients can rapidly improve and such early improvement may result in better progression of treatment.