According the problems of natural gas hydrates drilling fluid refrigeration system in the using process, such as improper manual operation, system paralysis caused by some abnormal factors of the equipment and frequent manual switching on and off of refrigeration cryogenic medium circulating pump, the intelligent temperature control unit was added based on the original system to improve the automation degree of drilling fluid refrigeration system for natural gas hydrates. The important hidden dangers of the refrigeration process are solved to ensure the normal process of drilling fluid refrigeration.