Introduction: Vitamin K, discovered in the 1930s, is a very important compound for the human body, performing many functions. The most well known of them are calcium homeostasis and coagulation. Nowadays it is apparent that many more beneficial multiorgan aspects of vitamin K exist.The aim of the study was to review the properties of vitamin K and to show its potential therapeutic value.Materials and methods: Medline databases (PubMed) and other scientific sources were searched.Results: Vitamin K shows a multifaceted effect on the proper functioning of the human body: preventing coronary vessel calcification, maintains normal blood pressure, has neuroprotective effects, reduces the risk of myocardial infarction, slows the process of osteoclastogenesis, and influences the production of bone reabsorption factors. In addition, vitamin K supplementation has been shown to reduce the risk of hepatocellular carcinoma (HCC) by interfering with tumour cells cycle and inducing their apoptosis. The pro-apoptotic activity of menaquinone is not limited to HCC only, but also to other cancers such as glioblastoma multiforme, breast cancer or bladder cancer, which reveals the importance of vitamin K in oncology. Possibly, introduction of vitamin K to the therapy may improve malignancy treatment outcomes.Conclusions: Vitamin K derivatives participate in many metabolic pathways of the human body. Their multifaceted activity may be used both in prevention of many diseases and in their potential treatments. However, further multicentre studies are necessary to understand better possible therapeutic properties of vitamin K derivatives.