As per the 2015 Census, more than half of the South Korean population (56.1%) is irreligious and doesn’t affiliate with any religion. Among organized religions, Christianity has the largest number of adherents, followed by Buddhism. 

Chrisanity in South Korea

Chrisanity is the largest religion in South Korea and 27.6% of the population were Christians (19.7% identified themselves as Protestants, 7.9% as Roman Catholics). Among Christian denominations, Presbyterianism is the largest. About nine million people belong to one of the hundred different Presbyterian churches; the biggest ones are the HapDong Presbyterian Church, TongHap Presbyterian Church, and the Koshin Presbyterian Church. South Korea is also the second-largest missionary-sending nation, after the United States.

Buddsimim in South Korea

Buddsimim is the Second largest religion and it is followed by 5.5% of the population. Buddhism was introduced to Korea in the 4th century. and once its dominant religion but declined rapidly in modern times.

Others

Other religions include Islam, Won Buddhism, and a variety of indigenous religions, including Cheondoism (a Confucianizing religion), Jeungsanism, Daejongism, Daesun Jinrihoe, and others. Islam is followed by 130,000 and mostly migrant workers from Pakistan and Bangladesh but including some 35,000 Korean Muslims

Religion percentage in South Korea (Census 2015)

Source: Census 2015

Projected Religious Composition (2010-2050)

The religious landscape of South Korea is marked by a steady increase in Christianity, while Buddhism is gradually declining. The unaffiliated population remains the largest, indicating a strong secular or non-religious trend in South Korean society. Folk religions continue to have a minor presence, while “Others,” including Muslims, remain a small but slightly growing group.

Source: PEW research center

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