Ong Tee Keat (simplified Chinese: 翁诗杰; traditional Chinese: 翁詩傑; pinyin: Wēng Shījié; Pe̍h-ōe-jī: Ong Si-kia̍t; born 22 November 1956) is a Malaysian politician who served as the Minister of Transport in the Barisan Nasional (BN) administration under former Prime Ministers Abdullah Ahmad Badawi and Najib Razak from March 2008 to June 2010, Deputy Minister of Higher Education in the BN administration under former Prime Minister Abdullah Ahmad and former Minister Mustapa Mohamed from February 2006 to March 2008, Deputy Minister of Youth and Sports in the BN administration under former Prime Ministers Mahathir Mohamad and Abdullah Ahmad as well as former Ministers Hishammuddin Hussein and Azalina Othman Said from December 1999 to February 2006, Deputy Speaker of the Dewan Rakyat under former Speaker Mohamed Zahir Ismail from June 1990 to November 1999 and Member of Parliament (MP) for Pandan from March 2004 to May 2013 and for Ampang Jaya from January 1989 to March 2004. He is a member of the opposition Heritage Party (WARISAN) and was a member of the Malaysian Chinese Association (MCA), a component party of the ruling BN coalition. He also served as the 8th President of MCA from October 2008 to March 2010.

The son of a fishmonger, Ong was an active grassroots MCA member even while at varsity. Educated at Confucian High School in Kuala Lumpur, Ong went on to the prestigious Methodist Boys' School for Form Six studies. Six years after graduating as a mechanical engineer, and while enjoying a lucrative post at an engineering firm, he quit to become political secretary to the then Housing and Local Government Minister Tan Sri Dato' Sri Lee Kim Sai in 1986.

Ong is married to Puan Sri Datin Sri Chooi Yoke Chun and has three daughters. Despite being Chinese educated, Ong is fully trilingual in Mandarin, English and Malay.

Ong won several literary awards for his works was once a columnist for Chinese daily Sin Chew Jit Poh. His articles ran from 1979 to 1986.

After becoming a full-time politician 1989, he contested the Ampang Jaya parliamentary seat in the 28 January 1989 by-election, upon the resignation of incumbent, Lim Ann Koon. He faced a tough challenge in his maiden effort to be a member of parliament when he was pitted against former Selangor Menteri Besar Datuk Harun Idris who was standing on a Parti Melayu Semangat 46 (S46) ticket. Ong beat the former Umno strongman by 4,500 votes. He went on to hold the seat for four terms before contesting and winning the newly created Pandan parliamentary seat in the 2004 general election. He successfully defended the seat in the 2008 general election.

When Ong was MCA Youth chief, he criticised the party top brass for the decision in 2002 to acquire Nanyang Press Holdings Bhd. A few years later, he was censured by the Cabinet for speaking out at the shoddy renovation work at a Chinese school in Muar, Johor.

Ong was appointed to the federal Cabinet after the 2008 election, as the Minister for Transport. He had previously been Deputy Youth and Sports Minister and Deputy Higher Education Minister.

In October 2008, Ong was elected MCA president, while Datuk Seri Dr Chua Soi Lek was elected deputy president. This set forth a tumultuous partnership, and eventually Dr Chua was expelled from the party by the Disciplinary Committee for his involvement in a sex scandal.