1Mr. Liang sicheng had suggested that the brick and masonry pagodas evolution could be divided broadly into three periods: "the Period of Simplicity, or the Period of Square Plan (ea.500-900)；The Period of Elaboration, or the Octagonal Plan (ca.1000-1300)；and the Period of Variety (ca.1280-1912)." Mr. Liang also said: "The Period of Elaboration may be tentatively set from the end of tenth of the thirteenth centuries, that is, covering the Five Dynasties and the Northern and Southern Sung dynasties, as well as the Liao and Chin dynasties" Following these statements, this paper tries to describe "the Period of Elaboration" more concretely and does special research on the brick pagodas of the Five Dynasties and the Song dynasty. A practical background of this paper was the restoration of Miaotong-Pagoda in Lianshui County of Jiangsu Province, which was built originally in Song dynasty and had been demolished in the civil war in 1948. And besides Miaotong-Pagoda, several other Song-pagodas in Jiangsu Province and Shanghai city also have been on-the-spot investigated and studied. Relying on these case studies and relative literatures, the paper is an attempt to sum up the knowledge of the pagodas of song-dynasty. In actually, its almost a collection of a series of notes about Song-pagoda which are organized in a frame as follows: 1、Study of the evolution of pagodas between Tang and Song dynasties.(Chapter 3) The paper analyzed the technical prerequisite and historical tendency that had lead to the reformation of the pagodas between Tang and Song dynasties.About 30 pagodas including Miaotong-pagoda etc.built during the early Northern Song dynasty have been collected and arranged in a queue by the building age in order that the variance of the prevailing styles and technical exploration in this period almost may be seen. The dynamic developmental process of pagodas building also can be showed in some degree. 2、Analysis of the technical and artistic generative mechanism of brick pagodas of Song dynasty. A、The technique and workmanship of the brick in Song -pagodas building.(Chapter 4) The achievements of the song-pagodas based on the mature technique of brickwork, especially the technique of imitating the timber construction faithfully with bricks.The paper reveals the particular value of the brickwork and the unique brick decorative system of the song-pagodas. B、The generative mechanism of the outward appearance and internal construction of Song-pagodas.(Chapter5) The Song-pagodas characterized by the appearance that seems“mellowed with grace and elegance”. The paper tries to give rational analysis of its formal logic and the mechanism of its graceful entasis and classical silhouette. Instead of the simply hollow shell of brick like the Tang-pagodas,the Song-pagodas characterized by2 “the introduction of both horizontal and vertical masonry interior divisions in the form of galleries and built-in stairs.”The paper analyzed the key thoughtway which brought this breakthrough and the basic mechanism of the flexible and diversified internal space of the Song-pagodas. C、Decomposed structural study of the brick pagodas of Song dynasty.(Chapter6) From platform foundation below a pagoda to the Ksetya on the top of a pagoda,some important structural parts are studied separately.The overhanging eaves supported by brackets and the surrounding balcony,as the features of a Song-pagoda, are detailed discussed.As one important type of song-pagodas, the structure of the wooden-clothed brick pagodas(with wooden waist eaves)is studied particularly. 3.Study of the under-ground palace and the foundation of the Song-pagodas (Chapter 2) The traditions that higher value was set on repairing or rebuliding an old pagoda than on budding a new one should be due to the underground palace where a root of pagoda religiouslife had been imbed. Besides the architectural types and value of the underground palace,the paper also discusses how to protect and revive them in pagndasrebuilding based on the referetial expetiences of Miaotong-pagoda. 4.Study of the culture of pagodas building in Song-dynasty and the custom of pagodas maintenanceandrestoration after Song-dynasty(Chapter7) According to the information from relative lgeratures and relics, the paper tries to describe the genuine social condition of the pagodas building in Song dynasty. And it pays more altertion to the traditional cussom of pagodas maintenance and restoration. As a typical example of restocation of pagodas,Miaotong pagodas rebuilding is ail-aromld recorded and compared with Leifeng-pagoda in order to show different models of pagodas restoration. 5.Discussion of the relationship between the typas of pagodas and elativc Buddhist sutra (Chapter1) As an aditional study to trace the origin of the pagodas meanwhile the study of Soag-pagodas. the paper tries to analyze systematically how the Chinese pagodas had been influenced by the relative Buddhist sutra. Keywords: the pagodas, brick pagodas, the architecture of the Song Dynasty, maintenance and restotation of pagodas.