Ectoin,also known as tetrahydromethylpyrimidine carboxylic acid,is an osmotic pressure protective substance widely present in halophilic and halotolerant bacteria.In this paper,the application of ectoin in the field of skin care was reviewed.The cell repair characteristics of ectoin and its mechanism and application in moisturizing,whitening,anti-inflammatory and light protection were summarized.It was expected to provide a reference for the further development and application of ectoin in the field of skin care.