Prince Xiao of Liang 梁孝王 (died 144 CBE), personal name Liu Wu 劉武, was a son of Emperor Wen 漢文帝 (r. 180-157 BCE) and a brother of Emperor Jing 漢景帝 (r. 157-141 BCE) of the Former Han dynasty 前漢 (206 BCE-8 CE).
In 178 he had been made Prince of Dai 代, in 176 he was shifted to the princedom of Huaiyang 淮陽, and in 168 to the princedom of Liang 梁. During the rebellion of the Seven Princes, he supported the emperorship of his brother and was able to ward off the attacks from the princedoms of Wu 吳 (see Liu Pi 劉濞) and Chu 楚 in the south. For this support he received the greatest honours from the Emperor and was allowed to mount the same carriage.
From then on, he became very arrogant and over-confident in his activities. The richness of his domain allowed him to feed numerous retainers at his court, like Yang Sheng 羊勝, Gongsun Gui 公孫詭, or Zou Yang 鄒陽. When Emperor Jing deposed his heir apparent, Prince Li 栗太子, the Empress Dowager suggested naming Liu Wu the heir of his brother, but Yuan Ang 袁盎 resisted this with of the Empress Dowager. Enraged by this stubborn resistance, Liu Wu secretly prepared for the assassination of Yang Ang. The Emperor from then on, disappointed of the betrayal of his own brother, only rarely received him at court audiences.
Liu Wu died after 35 years of reign as Prince of Liang. His posthumous title is Prince Xiao 孝王.