Ong, who had been an MCA member for over 30 years, confirmed his resignation to Malaysiakini.
“Needless to have any statement, for I am merely a small fry,” he told the portal today.
China Press had also carried a report on Ong’s resignation from the party, saying that it came into effect in January.
“With effect from Jan 2 this year, I’m no longer an MCA member. I feel it is not suitable to stay,” Ong told the Chinese daily.
When asked why he decided to leave the party, Ong said he wanted to be “a normal citizen”.
He has no plans to join another political party, and would instead focus on his business and write a book.
“I’m not suitable for political games. I have been in politics for 36 years, since 1981,” he was quoted as saying.
According to China Press, Ong had hinted that some quarters did not want to see him contesting in the next general election.
The 61-year-old had served as Ampang Jaya MP for five terms.
Ong was appointed transport minister after the 2008 general election and was elected MCA president the same year.
But he lost both posts in 2010, after he was defeated by Chua Soi Lek in the party’s polls.