Halophilic microorganisms cope with environmental stresses by producing and accumulating compatible solutes. Ectoine is one of the most important members of compatible solutes which have extra protective properties compared to other compatible solutes. Ectoine attracts several scientific and commercial attention because of their multiple industrial applications. This brief review presents applications of ectoine as protectants of proteins that can be explained by the preferential exclusion model. Also, other application of ectoine as an enzyme stabilizer and drug for various diseases have also been reviewed. Further, the role of ectoine in stabilizing macromolecules and even whole cells against UV radiation, freezing, drying and high temperatures is briefly described. The ectoine biosynthesis genes are located in cluster ectABC. This paper also briefly described the regulation of these genes under environmental conditions. There are currently two technologies for producing ectoine called bacterial bio-milking and leaky mutant. Several tons of ectoine are produced each year using these methods. Finally, the limitations of the methods are mentioned.