SAITO Tama (1936-2017) is an independent folklore researcher who walked throughout Japan collecting folklores. Her collection covers a wide area including children's play, words, uses of plants, and events. She has also written many books, but her unique research has not been evaluated much until now.The Department of Intangible Cultural Heritage was donated with approximately 47,000 investigation cards of SAITO Tama in January 2017 and is in the midst of arranging them. By categorizing the cards according to keywords it is hoped that they may be searchable and utilized widely.SAITO Tama's collection related to folklore of children's play is numerous beyond comparison. In particular those about string figures compiled in Ayatori Itotori (Fukuinkan Shoten, 1982) and translated into English ("String Figures of Japan," Bulletin of the International String Figure Association ,11. 2004) is worth noting. Other than these, she has also collected information which is too close to people's daily life, such as what do they use when they defecate or urinate, that theycould not be considered subjects for academic study, although quite interesting from the point of view of folklore study.SAITO Tama also spent much effort collecting vocabulary, and it appears that using investigation cards was quite useful in arranging words that differed from one area to another. Using the enormous number of cards, she developed her own theory of etymology, avoiding simply accepting what a dictionary says.These investigations reflect in close detail the life style of the time when people's relation with nature was very close. The investigation cards are extremely valuable as record of lost customs, and transmit to the present the wisdom of our predecessors who utilized things that exist in nature. It is hoped that the arranging of these investigation cards will shed light on SAITO Tama and evaluate her work.