This article reviews the multifaceted roles of Vitamin K (VK) in preventing and treating infections, inflammation, and autoimmune diseases. VK, known for its coagulation properties, has been found to have significant benefits beyond blood clotting. The review highlights the potential of VK in managing conditions such as asthma, COVID-19, type 2 diabetes mellitus (T2DM), Alzheimer's disease (AD), Parkinson's disease (PD), cancer, aging, atherosclerosis, and autoimmune disorders like inflammatory bowel disease (IBD), type 1 diabetes mellitus (T1DM), multiple sclerosis (MS), and rheumatoid arthritis (RA). VK's mechanisms of action include anti-inflammatory and antioxidant activities, regulation of intestinal microbiota, and modulation of immune responses. The review also discusses the role of VK-dependent proteins (VKDPs) in these therapeutic effects. While VK shows promise in these areas, further research is needed to elucidate its mechanisms and optimize dosages for clinical applications.This article reviews the multifaceted roles of Vitamin K (VK) in preventing and treating infections, inflammation, and autoimmune diseases. VK, known for its coagulation properties, has been found to have significant benefits beyond blood clotting. The review highlights the potential of VK in managing conditions such as asthma, COVID-19, type 2 diabetes mellitus (T2DM), Alzheimer's disease (AD), Parkinson's disease (PD), cancer, aging, atherosclerosis, and autoimmune disorders like inflammatory bowel disease (IBD), type 1 diabetes mellitus (T1DM), multiple sclerosis (MS), and rheumatoid arthritis (RA). VK's mechanisms of action include anti-inflammatory and antioxidant activities, regulation of intestinal microbiota, and modulation of immune responses. The review also discusses the role of VK-dependent proteins (VKDPs) in these therapeutic effects. While VK shows promise in these areas, further research is needed to elucidate its mechanisms and optimize dosages for clinical applications.