Both of the "theory of classification of teaching" and practice ways of T'ien-t'ai Buddhism are very copious and complete. But there is still no paper which gathered and showed all of the practice ways of T'ien-t'ai Buddhism. Besides, it is known that "Four Teachings" (四教) and "Threefold Contemplation" (三觀) are the essentials of T'ien-t'ai Buddhism. But they were not established by Zhi-yi (智顗) at the beginning "Perfect-teaching" (國教), which is noticed the most, includes "Four Forms of Samadhi" (四種三昧). The characteristics of "Four Forms of Samadhi" were different between Zhi-yi's books of earlier and later stage. These all are important topics to know well about T'ien-t'ai Buddhism. This paper will collect all the practice ways of T'ien-t'ai Buddhism by analyzing all the Zhi-yi's books of his earlier stage and shows the development of "Four Teachings" and "Threefold Contemplation," the characteristics of "Four Forms of Samadhi," and each practice ways belongs to which teaching of "Four Teachings." According to my research, the practice ways of "Fang-dang Samadhi" (方等三昧) belongs to "Contemplation of Empty" (空觀). In "Shi-chan-bo-luo-mi" (釋禪波羅蜜), Zhi-yi developed a complete system of practice, based on the theory of his teacher Hue-si (慧思), "Da-tsu-du-lun" (大智度論) and many scriptures "Threefold Contemplation" was mentioned in "Shi-chan-bo-luo-mi," but the major way of contemplation in was still "contemplation of Empty." The way of contemplation in "The Ritual of Lotus Samsdhi" (法華三昧懺儀) belongs to "Contemplation of Empty" too. Both of the ways of contemplation of "Fang-dang Samadhi" and "The Ritual of Dharma Lotus Samadhi" were not practice ways of "Perfect-teaching." But they became to be practice ways of "Separate-teaching" (別教) and "Perfect-teaching" in "Shi-chan-bo-luo-mi." The statement that "Six Marvelous Practice Ways" (六妙法門) was the representative work of "Indefinite Way of Samadhi and Contemplation" (不定止觀) was not made by Zhi-yi, but perhaps made by Guan-ding (灌頂). The evolution of the theory of "Threefold Contemplation" appeared in "Indefinite Way of Samadhi and Contemplation." But the theory of "Threefold Contemplation in One Single Mind" (一心三觀) didn't appear till now. The saying of "Four Teachings" (四教) wasn't mentioned in all Zhi-yi's books of his earlier stage.
