We investigated the factors related to taste, the process and the motives of one's taste in order to make a behavioral approach to the problem. The methods were as follows. Inquiries about 1456 girl students (age 18-20) in all districts of Japan and 600 people in and around Tokyo were made in June 1971. The questionnaire was printed on punch card. The subject under investigation was fish of which horse mackerel was chosen. The cookery of horse mackerel was grouped into six types—“raw”, “boiled with soy”, “broiled with salt”, “fried”, “meunière” and “dried”. The levels of taste were divided into four grades—“care for”, “neither care for nor dislike” “dislike” and “have no experience of eating”. The methods of analyses were the third type of quantification, presumption of the percentage, χ2 method, Rigit method and t tests. The results were as follows. 1. Environmental factors and taste. According to the geographical groups divided by the presence of the sea and regional groups divided by the yield of horse mackerel, in case the districts were not surrounded by the sea having a small yield of horse mackerel, the percentage of those who cared for horse mackerel was high. As for the difference of the residential environment, industrial districts generally showed a high percentage of those who cared for it, and residential sections and commercial districts presented a marked contrast to industrial districts. As for the home environment, in case of the grandmother living in the same house preparing meals, many tended to dislike “boiled with soy sauce”. Concerning the occupations of parents, whether the mother was a working woman or not had greater influence on the formation of children's taste than occupations of the father. 2. Psychological factors (character trait and character type) and taste. According to the trait of character by the Y-G Personal Inventory, it could be observed that levels of taste varied with character types. We might possibly assume that the levels of taste of E-type was low, and that of D-type was high. 3. Physiological factors (sex and age) and taste. The percentage of taste of men were generally higher than that of women. That is because men are apt to take horse mackerel with Sake (Japanese Wine). People at older age inclined to have a preference for it, especially showing a marked tendency to care for “broiled with salt” and “dried”. 4. The reasons of taste and association observed from the sensual factors and psychological factors. Good taste was one of the reasons why girl students, high school students and the general public cared for horse mackerel. For “dislike” girl students and high school students attributed their dislike to the smell and psychological reasons, and the general public to the smell and bad taste. Association. The words of association varied with likes or dislikes. We could group the cookery into two types—seasonal cookery and cookery in all seasons. 5. The change of taste. One's taste varies. We observed many people who changed taste grade from dislikes to likes. In general, they tended to change their taste grade during junior high school and senior high school days. It may be concluded that nutritional education adapted towards one's taste will be needed. 6. The patterns of one's taste from multi-dimensional analysis. The correlation ratios between the answers obtained and answerers were high. The patterns of the levels of taste and types of cookery were made clear by checking the answers. The pattern of the individual relevant factors was not clear, but we could get a vague idea.