He was born in Yongchun County, Southern Fujian Province in China and migrated to the then Malaya (now Malaysia) in 1903.

He continued building his wealth through establishing retail shops, and later through investment in rubber estates and commercial properties in Manjung District and as far as Betong in Thailand.

The wealth he created would later be used towards various charity and education projects in Manjung District, and in particular, Sitiawan town.

[1][2][3] Ong was born on 21 November 1884 in China, in Jindou, Yongchun County, Southern Fujian Province.

In 1905, he moved to the Ipoh area, starting his own business as a "thing-tong" man, peddling clothes, toys, and shoes among other things, selling to the tin-mining community in Ipoh and surrounding towns including Lahat, Menglembu, Pusing, Gopeng and Tronoh.

Ong then moved to Sitiawan in 1908 where he established several retail shops and in the surrounding area including Changkat Jering.

[6] Ong contributed to social welfare through charitable works which intertwined with his education projects.

[7] In 1913, at the age of 29, Ong established the Aik Tee Recreation Association (Aik Tee Soo Poh Seah) in Sitiawan, for the purpose of enabling the migrant community to socialise, exchange news, read books and newspapers, and for the youth to take part in sporting activities.

Two years after his death, the Association posthumously recognised his contributions to the community with a lifetime achievement award.

In 1931, after years of drought and severe flooding in China, he, again as Chairman of the Sitiawan Fundraising and Disaster Relief Committee, raised money and materials in aid of victims.

[13][16][17] When the Sino-Japanese War (Chinese: 甲午战争) broke out in 1937 between China and Japan, Ong organised a boycott of Japanese goods.

Fundraising brought Ong to towns in many parts of Malaya, to Singapore and Betong, Thailand.

[20] Before 1935, there were four dialectic schools in Manjung District, each with its own junior high school section catering for their own clan - Chung Cheng for the Hokkien, Kuok Min for the Kutien, Uk Dih for the Hockchew (Fuzhou) and Min Teik for the Hockchia.

The community leaders chose the name "Nan Hwa" to remind students that their ancestors migrated from China to settle in Nanyang.

Ong personally donated $3,000 to purchase a piece of land along Kampung Koh Road.

[23] As Chairman of the Fundraising Committee, Ong solicited donations from the public and businesses in towns throughout Malaya and in Singapore to build new classrooms, teachers' room, and amenities and office administration block.

a substantial donation from Haw Par Brothers was solicited by Mr Ong Seok Kim, and a school hall was erected and named after the donors.

In the midst of the then prevailing chaotic situation, some community leaders led by Mr Ong Seok Kim visited Nan Hwa High School, with the purpose of reopening the institution for classes to resume as soon as possible.

The re-organised Management Committee of Nan Hwa High School, Sitiawan, under the chairmanship of Mr Ong Seok Kim, .

raised the needed funds to repair and renovate the existing premises and also to build additional classrooms to meet the fast growing student population after the War.

"[25] In 1951 Ong, together with Saw Cheng Chor (Chinese: 苏清楚), founded Ping Min Free School in Lumut, a coastal town in the Manjung District.

[26] In June 1953, Ong, then 69 years old, and Shen Ding-yuan (Chinese: 沈丁元), founded Dindings High School.

In his diary, Ong recounted the fundraising activity as “full of painfully hard work”.

Members of the Committee, led by Ong, had financed their own expenses in their trips out of town to solicit for donations.

[31] Ong was appointed a Justice of the Peace (J.P.) in 1963 by the Sultan of Perak; and awarded the Kesatria Mangku Negara (KMN) by the Yang di-Pertuan Agong in 1964,[13][32][33] a few months before his passing.

The main objective of the Fund was to provide bursaries and scholarships to less fortunate local students to further their studies.

Since its inception, the Fund has awarded financial assistance to thousands of students of different ethnicity from schools in the Manjung District.

It had also provided financial assistance to students of Sitiawan in 1968 and Pangkor Island in 1983, who were victims of fire which destroyed their houses.