Moses ben Jacob Cordovero (Hebrew: משה קורדובירו Moshe Kordovero; 1522–1570) was a central figure in the historical development of Kabbalah, leader of a mystical school in the Ottoman Empire in 16th-century Safed, located in the modern State of Israel. He is known by the acronym Ramak (רמ״ק).

After the medieval flourishing of Kabbalah, centered on the Zohar, attempts were made to give a complete intellectual system to its theology, such as by Meir ben Ezekiel ibn Gabbai. Influenced by the earlier success of Jewish philosophy in articulating a rational study of Jewish thought, Cordovero produced the first full integration of the previous differing schools in Kabbalistic interpretation. While he was a mystic inspired by the opaque imagery of the Zohar, Cordoverian Kabbalah utilised the conceptual framework of emanating cause and effect from the Infinite to the Finite in systemising Kabbalah, the method of philosophical style discourse he held most effective in describing a process that reflects sequential logic and coherence. His encyclopedic works became a central stage in the development of Kabbalah.

Immediately after him in Safed, Isaac Luria articulated a subsequent system of Kabbalistic theology, with new supra-rational doctrines recasting previous Kabbalistic thought. While Lurianism displaced the Cordoverian scheme and became predominant in Judaism, its followers read Cordoverian works in harmony with their teachings. Where, to them, Lurianism described the "World" of Rectification, Cordovero described the pre-Rectification World. Both articulations of the 16th-century mystical Renaissance in Safed gave Kabbalah an intellectual prominence to rival medieval Jewish rationalism, whose social influence on Judaism had waned after the expulsion of Jews from Spain.

The name Cordovero indicates that his family originated in Córdoba, Spain, and perhaps fled from there during the expulsion of 1492 ensuing from the Spanish Inquisition. His Hebrew signature, however (Cordoeiro), strongly suggests a long-lasting residence in Portugal.

Moses was either born in or moved to Safed in the Land of Israel, the city that was soon to become famed as a center of Kabbalah and mystical creativity. Although not involved in mystical studies until his twentieth year, he soon gained a reputation as an extraordinary genius and a prolific writer. Besides his knowledge in Kabbalah, he was a Talmudic scholar and a man of commanding mastery in Jewish philosophy who was respected in these fields. Contrary to popular belief, however, he was not one of the rabbis who received the special semikhah ('ordination') from Jacob Berab in 1538, alongside Joseph Karo, Cordovero's teacher of Halakha, Moses ben Joseph di Trani, Yosef Sagis, and Moshe Alshich. As a whole, Cordovero's contributions to posterity were in speculative and performative Kabbalah; however, during his lifetime, he was the renowned head of the yeshiva for Portuguese immigrants in Safed.

According to his testimony in the introduction to Pardes Rimonim (Orchard of Pomegranates), in 1542, at the age of twenty, Moses heard a "heavenly voice" urging him to study Kabbalah with his brother-in-law, Shlomo Alkabetz, composer of the mystical song "Lecha Dodi". He was thus initiated into the mysteries of the Zohar. The young Moses not only mastered the text but also decided to organize the kabbalistic themes leading to his day and present them in an organized fashion. This led to the composition of his first book, Pardes Rimonim, which was completed in 1548 and secured his reputation as a brilliant kabbalist and a lucid thinker. The Pardes, as it is known, was a systematization of kabbalistic thought up to that time and featured the author's attempt at reconciling early schools with the conceptual teachings of the Zohar to demonstrate an essential unity and self-consistent philosophical basis of Kabbalah.

His second work, a magnum opus entitled Precious Light (אור יקר, Or Yāqār), was a 16-volume commentary on the Zoharic literature in its entirety and a work to which the Ramak had devoted most of his life. Some other books for which he is known are the Tomer Devorah (Palm Tree of Deborah), in which he utilizes the kabbalistic concepts of the sefirot to illuminate a system of morals and ethics; Ohr Neerav, a justification of and insistence upon the importance of Kabbalah study and an introduction to the methods explicated in Pardes Rimonim; Elimah Rabbati, a highly abstract treatise on kabbalistic concerns revolving around the Godhead and its relationship to the sefirot; and the Sefer Gerushin, a short and intimate composition which features the highly devotional slant of Cordovero, as well as his asceticism and religious piety. Certain parts of Cordovero's works are still manuscripts, whereas his existing writings suggest that he had many other compositions that he either intended to write or had written, but which were lost.

Around 1550, he founded a Kabbalah academy in Safed in the Damascus Eyalet of Ottoman Palestine, which he led for approximately twenty years until his death. He is buried in the Old Cemetery of Safed. His disciples included Eliyahu de Vidas, author of the Reshit Chochmah (Beginning of Wisdom), and Chaim Vital, who later became the official recorder and disseminator of the teachings of Isaac Luria.