Early Buddhist rock cave temples of India, in spite of being an origin of Buddhist temples, has little been studied in Korea. After field studies and an interpretation of their forms in conjunction with religious life, precedent theories are supplemented and refuted as follows. Starting from the 2nd century B,C., Buddhist ascetic disciples digged residential rock caves, called vihara, for protection from monsoon rain and hot weather, A typical arrangement was settled -a courtyard type, with 3 side rows of tiny one-person bedroom and a front veranda with columns. Also digged were Chaitya caves, in line with viharas, to worship, which is the tumulus of Buddha's relics. I suggest that the original type of chaitya a simple circle cave with a stupa, suitable for circumambulating ceremonies. I refute the existing theory presenting Barabar caves of Ajivika as a chaitya origin, featuring empty circular room without a stupa. I also interpret a typical apsidal plan as being a simple result of adding a place of worshipping rites in front of the stupa. Enclosing columns around a cylindrical stupa is a result of reinforcing both the divine space and circumambulating ceremonies, with elongation toward hall. Finally the chaitya came to have a grandeur apsidal plan with high vault ceiling nave and a side aisle as in Western cathedrals with large frontal horseshoe arch windows. The Buddha image, which had become a new worshipping object, was integrated into the stupa and interior surface. First the stupa and then the statue was introduced to residential Viharas. Therefore, I suggest that the vihara should be renamed as 'chaitya' as a worshipping place, by establishing statue rooms without bedrooms at all. The functionally changed vihara is similar in form to a 'rectangular type of chaitya', little known and developed in different routes. A columned inner courtyard gradually becama an offering place, like Hindu mandapa, Buddhist caves ware changed to a kind of Tantric and Hindu temple by means of statue worshipping offering rituals.