Changes in sweetness perception in 74 nonobese 18-36 year old women in various phases of their menstrual cycles were assessed. Of these 39 were using an oral contraceptive. Subjects were tested with each of 3 sugar solutions of .5 1 and 2 molar strengths. Solutions were held in their mouths for 15 seconds and then spit out. Between taking the solutions a piece of cheese was given to neutralize the taste of the previous solution. Immediately subjective sensation of degrees of pleasant or unpleasantness were expressed. Differences in phases of the menstrual cycle were related to sweetness preferences (p less than .05). Those in the menstrual phase preceding the premenstrual period found the sugar solutions less pleasant than did those in earlier phases. Some variations were observed but they were not correlated with use of oral contraceptives. Variations of hormone level were thought to be significant.