The present study categorized nicknames of Japanese undergraduates and examined their feelings toward nicknames. Results categorized nicknames into 12 categories: "nickname related to one's name", "name with -chan" (e.g., Yuki-chan), "famous person", "name with -kun or -san" (e.g., Yuki-san), "appearance", "nickname related to one's nickname", "psychological attributes", "another reading on Kanji of one's name", "occupational role", "object", "hometown", and "unidentified". And results indicated that undergraduates felt "nickname related to one's name", "name with -chan", and "name with -kun or -san" happier than "famous person" and felt "name with -chan" happier than "appearance".