The inventory making of intangible cultural heritage of ethno-medicinal plants used among ethnic communities in upper northern Thailand for the purpose of savc-guarding and conservation has been initiated since the year 2000 supported by Thailand Research Fund. The process is based on the bottom-up inventory-making procedure and participatory action research among healers and indigenous scholars from all ethnic communities to explore and revise their existing knowledge of using medicinal plants while inventory and mapping of the existing medicinal plants were also undertaken and identified. There are at least 1,200 varieties still wildly exist and support the healers for their daily used.The upper northern Thailand so call "Lanna" with more than 800 years history comprise with the most diverse ethnic groups. The Lanna people have their own intangible cultural heritage (ICH) for traditional medical practices and medicinal herbs usage which reflect views, wisdom, knowledge and belief of the Lanna people in relation to maintain their "good health".