This research examines the three dimensions of socio-cultural changes that influenced religious cognition in the modernization period of Korea. The first dimension is structural differentiation in the society and culture. From the standpoint of traditional religion. religions in the modernization period experienced the so-called 'secularization' in the areas of education, medicine and politics. And the concept of religion itself was significantly reduced in its scope of meaning, On the other hand. however, it might be also said that the change of religious cognition in the modernization period means the separation of a pre-modem and inessential layers from religion. Thus we might think only the primordial essence of religion survived and such a change was a purification process of religion itself. The second dimension is social stratification in the country. The traditional Confucian society critically broke down in a hierarchical confusion at that times. This means that religion can no longer be monopolized by the high-ranking government officials but is recognized as a natural right for everyone. And this kind of 'popularization of religion' has guaranteed the universal notion of religion in the Korean situation since that time. The third dimension is the influx of Western culture. Above all Christianity I by introducing various Western cultural aspects to Korea, destroyed Eastern provincialism established by the multiplicity of traditional religions and expanded the concept of religion to the cross-cultural context. It might be said that this trend stimulated indigenous religious movements. resulting in a religious pluralism in its modern sense which brought about the foundation for a dynamic situation of competition. It is the reflexive ethos of religious cognition derived from this modern religious pluralism that gave rise to the religio-comparative and critical studies of religion early in modem Korea.