In recent years，the research on environmentally friendly lubricants for drilling fluids has developed rapidly. In this paper，the types，mechanisms of action and the latest research progress of environmental lubricants used in drilling fluids at home and abroad were reviewed，and a variety of biological toxicity evaluation methods suitable for lubricants were compared. In order to ensure the accuracy of environmental protection indicators，it was recommended to conduct multiple evaluation methods at the same time and to achieve both EC₅₀ and LC₅₀ data. The development trend of environmentally friendly lubricants in the future was analyzed，especially for the high-efficiency，environmentally friendly and high-temperature resistant lubricants，and the future research prospects of synthetic ester lubricants was predicted.