Participants in blockchain voluntarily provide health knowhow (Medi story) and record their individual health information (Medi Info) on blockchain to share it with other people and prove its usefulness. MEDIKEY is a blockchain network that integrates AI, IoT and Big Data that represent 4th industry. It uses big data for Medical Health Wellness and is applied to the entire medical field. As a result, participants are rewarded for sharing information and performing Medi-Mission. Basically, it is the information-sharing program voluntarily provided by chronic patients, people on diet and PT and fitness participants.