Chronic diseases such as diabetes mellitus, cardiovascular disorders, chronic respiratory diseases, hypertension, and neurological conditions are responsible for the majority of global morbidity and mortality. Traditional healthcare models often rely on periodic clinical assessments, limiting continuous disease surveillance and early intervention. Wearable devices have emerged as innovative digital health tools capable of continuously monitoring physiological parameters in real time. These devices provide valuable information regarding heart rate, blood pressure, blood glucose, oxygen saturation, physical activity, sleep patterns, and other health indicators. This review examines the role of wearable devices in chronic disease monitoring, discusses technological advancements, clinical applications, benefits, limitations, ethical concerns, and future directions. The integration of wearable technology with artificial intelligence, telemedicine, and electronic health records has the potential to revolutionize chronic disease management and improve patient outcomes.