理查一世（英语：Richard I，1157年9月8日－1199年4月6日），中世纪著名的英格兰国王以及十字军名将。因其在战争中总是一马当先，犹如狮子般勇猛，因此得到「狮心王」的称号，英文：Richard the Lionheart。纵其一生戎马弓刀，热忱投身于十字军东征的许多战役之中，为第三次十字军东征作出了卓越贡献；甚至还于阿苏夫一役中击溃穆斯林大军，打破了穆斯林统帅萨拉丁「不败军神」的神话，使其成为中世纪最杰出的将领之一。

Richard I (8 September 1157 – 6 April 1199) was King of England from 6 July 1189 until his death. He also ruled as Duke of Normandy (as Richard IV), Duke of Aquitaine, Duke of Gascony, Lord of Cyprus, Count of Poitiers, Count of Anjou, Count of Maine, Count of Nantes, and Overlord of Brittany at various times during the same period. He was the third of five sons of King Henry II of England and Eleanor of Aquitaine. He was known as Richard Cœur de Lion or Richard the Lionheart because of his reputation as a great military leader and warrior. He was also known in Occitan as Oc e No (Yes and No), because of his reputation for terseness.