Habitats for the cold-adapted microorganisms represent a large proportion of the Earth’s area. Much of the oceans, which cover about 70% of Earth’s surface, are at an average temperature of -1 to +5 oC. Various mechanisms of adaptations to cold include cell membrane fluidity, genome plasticity,synthesis of cold shock proteins,and compatible solute accumulation. But these mechanisms of adaptations are not universal because of different ecological groups of psychrophiles and their niches. Recent progress in psychrophilic genomics, metagenomics, proteomics have helped a lot in understanding these adaptive mechanisms.Metagenomic and proteomic analyses have suggested that the cold-adapted enzymes have decreased internal hydrophobicity,H-bonding,proline content but increased surface unpaired charged residues. The genome sequence analysis of Colwellia psychrerthraea 34H has revealed different mechanisms, even for carbon and nutrient cycling. The comparative genome analysis suggested that psychrophilic life style is due to changes in overall genome and aminoacid composition, but, not by a unique set of genes.Cold induced proteins (CIPs) prevent formation of secondary mRNA structures during transcription/ translation coupling phases. Cold adapted enzymes have large conformational flexibility so as to increase KCat.Cold active gene products have a variety of applications in molecular biology,foods,cosmetics,and textiles.