This paper is a review of inborn errors in galactose metabolism with special attention being paid to practical aspects of this problem. The authors presented the history of experimental research on galactose metabolism in human body, patomechanisms of biochemical abnormalities and clinical course of the disease as well as the review of genetic papers regarding polymarphism of galactose-1-phosphate uridyl transferase, galactosemic variants in human population and the possibilities of early diagnosis and treatment of galactosemia.