Macroscopic examination of the urine has been used since time immemorial for the diagnosis and prognosis of nearly every disease. Although the great fathers of antiquity, such as Hippocrates and Galen, were involved in the practice, it reached its heights during the Middle Ages. This article divides the Middle Ages into three periods -early, middle and late – and studies the use of the method and the contributions of its particular practitioners in the eastern part of the former east Roman Empire (Byzantium). Uroscopy achieved there a more scientific status than in Western Europe, at least during the first two periods of the Middle Ages, and it also influenced heavily Arabic and Jewish medicine. However, Byzantine urosocopy was mainly based on ancient Greek knowledge and was open to progressive influences by medical progress in all its neighboring countrie