In order to protect the information security of intelligent oilfield, the information security protection method of intelligent oilfield based on blockchain technology is proposed. Aft that intelligent oilfield information is subjected to reasonable cluster, different kinds of intelligent oilfield information data sets are constructed, the intelligent oilfield information data set are cleaned by using a data cleaning technology based on active learning, the intelligent oilfield information is encrypted and transmitted by using a data encryption transmission method based on a blockchain and an artificial intelligence technology, and the intelligent oilfield information is put into a blockchain for distributed storage; Information visitors need to obtain authentication certificates before they can reasonably access intelligent oilfield information. The results show that the application of this method in the information security protection of intelligent oilfield can significantly improve the security of intelligent oilfield information and avoid network attacks and illegal access.