The Secretum Secretorum is a medieval treatise also known as Secret of Secrets, or The Book of the Secret of Secrets, or in Arabic: ?堛塈堥 堻堭 塈?堧堻堭塈堭??(Kitab sirr al-asrar), or the Book of the Science of Government: on the good ordering of statecraft.

It is a mid-12th century Latin translation of a 10th-century Arabic encyclopedic treatise on a wide range of topics, including statecraft, ethics, physiognomy, astrology, alchemy, magic and medicine. It was influential in Europe during the High Middle Ages.