The main role that cold-adapted microorganisms can play at low temperature is biodegradation of organic matter. Some of these microorganisms are pathogenic for plants and animals. Cold-adapted microorganisms cause many problems in the storage of food products. They are also attractive biocatalysts for many biotechnological purposes, because of high activity at low temperatures and increased thermolability. The mechanism of thermal adaptation is insufficiently recognised. The most common adaptations of cold-adapted microorganisms are: elevated flexibility of their molecules, fatty acid composition of membrane lipids, protein conformation and functioning of enzymes. Undoubtedly, better knowledge on the physiology and genetics of cold-adapted microorganisms could be useful for enhancing their metabolic activity in natural environments or in the industry.