Liao Zhongkai (April 23, 1877 – August 20, 1925) was an American-born Chinese revolutionary. He was a close follower of Sun Yat-sen and was one of the foremost leaders of the Kuomintang (KMT) from its founding until his death. He is considered to have been part of the KMT's left wing and supported the First United Front between the KMT and the Chinese Communist Party (CCP). In August 1925, he was assassinated by members of the KMT's right-wing who were opponents of the First United Front.

Liao was born in 1877 in Alameda, California and received his early education in the United States. He was one of nineteen children. His father Liao Zhubin, who had five wives, was sent to San Francisco by the Hong Kong and Shanghai Bank.

Returning to Hong Kong in 1893, at the age of sixteen he studied at Queen's College from 1896. He married He Xiangning in 1897. He then went to Japan in January 1903 to study political science at Waseda University. In 1907 he went to Chuo University to study political and economic science.

Liao joined the Chinese Revolutionary Alliance in 1905 upon its founding and became the director of the financial bureau of Guangdong after the founding of the Republic of China.

In the early struggles of the party, Liao Zhongkai was arrested by Guangdong strongman Chen Jiongming in June 1922. After Chen's defeat Liao became Civil governor of Guangdong from May 1923 to February 1924, and then again from June to September 1924.

Following the Bolshevik Revolution, Sun Yat-sen began a correspondence with the Bolsheviks that grew into the First United Front between his movement, the CCP, and the Soviet Union. Liao Zhongkai strongly supported this move. Soviet advisors began arriving in Guangzhou and helped Sun organize a mass political party. Liao became one of the members of the provisional executive committee of the new Kuomintang (KMT), which met from October 1923 to early 1924. In February 1924, Liao was appointed to head the new Ministry of Labor, which was tasked with bringing the labor movement into the national revolution. He attempted to organize a "Guangzhou Workers' Delegates Conference" the following month, but was met with little interest from unions. It would take a year of hard organizing to build positive relations with the unions and infiltrate party members and sympathizers into the union leadership.

In May 1924, he became political commissar of the newly established Whampoa Military Academy. There, he was in charge of the political training of the future officers of the National Revolutionary Army. When Sun Yat-sen died in March, 1925, and Liao was one of the three most powerful figures in the Kuomintang Executive Committee, the other two were Wang Jingwei and Hu Hanmin. When Hu Hanmin's proposal for a National Government Council was accepted by the KMT's Central Executive Committee, Liao was chosen to be Minister of Finance on July 24. During this time he was considered to be a leader of the KMT's left-wing and strongly supported the First United Front. He was principled in his support of Sun's ideology of Minsheng in the Three Principles of the People.

Beginning with a dispute between Chinese students at Holy Trinity College and the school's administration, a wave of opposition to Christian schools spread through China in 1924. In August, Liao Zhongkai confounded the Anti-Christian Federation with Wu Zhihui. He would go on to oversee many of the anti-Christian demonstrations that spread through central China.