Kim Jae-sung (Korean: 김재성, born 3 October 1983) is a South Korean professional footballer who plays for Udon Thani.

Kim previously played for Bucheon SK and Jeju United.

Kim graduated from the same Football Academy College as Park Ji-sung. He has said that he used to train with Ji Sung Park as a teenager at the college.^{[citation needed]}

He has also had recent international duty call backs and was influential in the 3–1 victory over Japan in the 2010 East Asian Football Championship.^{[citation needed]}

On 9 January 2010, Kim made his first international cap for South Korea at the friendly match against Zambia.^{[citation needed]}