Data published in the period from 2000 to 2015 on chemical transformations of the major human bile acids (cholic, chenodeoxycholic, deoxycholic and lithocholic acids) and ursodeoxycholic acid are integrated and described systematically. Characteristic features of their structures, biosynthesis, main sources and biological functions are considered. The data on chemical transformations of the indicated bile acids include reactions involving modifications of the side chain or the steroid nucleus. The biological activities and applications of these derivatives are surveyed in brief. The bibliography includes 227 references.