This paper mainly expounds the scientific and technological achievements made in the Sui and Tang Dynasties from the following aspects.

During the Sui and Tang Dynasties, remarkable achievements were made in astronomical calendars. The Emperor's Calendar, compiled by Liu Zhuo, a famous astronomer in Sui Dynasty, uses quadratic equidistant interpolation method to calculate the movement of the sun and the moon, and the precession accuracy is higher than that in Europe. He also put forward the viewpoint of measuring the meridian length, denying the traditional saying that the shadow is an inch away. In the Tang Dynasty, the seven-character Long song Song of Heaven edited by Wang Ximing was widely circulated, which greatly promoted the popularization of astronomical knowledge. In Xu Ang's Xuan Ming Calendar in the Tang Dynasty, the intersection angle between the ecliptic and the equator was measured to be 23 U 65299 X 5', which was only about 0.5' lower than the modern theoretical value. Monks and their gatherings in kaiyuan period.

The Sui and Tang Dynasties also made great achievements in mathematics. Liu Zhuo, an astronomer in Sui Dynasty, created the quadratic interpolation formula with equal spacing for the first time when compiling the calendar, which was a major breakthrough in the history of mathematics. Wang Xiaotong was a famous mathematician in the Tang Dynasty. He devoted his life to the study of mathematics. His greatest contribution was to establish the Classic of Ancient Calculations on the basis of summarizing the previous research results. In this calculation, he put forward the positive root solution of cubic equation for the first time, which made outstanding contributions to the theory of ancient mathematical equations. Taishi Gong, Taishi Gong Li, Taishi Gong Arithmetic Doctor and Taishi Gong Zhu Professor Wang Zhenru were invited to annotate ten arithmetic classics. These ten arithmetic classics are Zhou Pian Arithmetic Classic, Nine Chapters Arithmetic Classic, Island Arithmetic Classic, Wu Cao Arithmetic Classic, Sun Tzu's Art of War, Xiahou Yang Arithmetic Classic, Zhang Qiujian Arithmetic Classic and Five Arithmetic Classics. There is also Han Yan's arithmetic "Xiahou Yang Shu Jing", which consists of 3 volumes and 83 cases, mostly for the mathematical knowledge and calculation skills commonly used by local officials and ordinary people. According to historical records, in addition to Wang Xiaotong, Li Monk and his party, there are Chen Congyuan, Long Deyi, Bian Gang, Liu and others.

In the Sui and Tang Dynasties, agriculture was particularly developed and achieved fruitful results. Emperor Wendi of Sui Dynasty began to implement the system of equal land, which greatly promoted the recovery and development of agricultural production. In the Tang Dynasty, the system of land equalization and rent adjustment was implemented, which rewarded reclamation, stabilized farmers' lives and developed agricultural production, and a social fashion of working for agriculture, mulberry, fashion and thrift emerged. The vigorous development of agricultural production has also promoted agricultural technology. Great progress has been made in farmland management techniques such as land preparation, soil conservation and expanding fertile fields. At that time, the technical problems of water diversion, drainage and irrigation were also solved scientifically. Qu Yuan's plough appeared in the Tang Dynasty, which is of epoch-making significance in the history of ancient ploughing. Tea production and production technology in the Tang Dynasty reached a high level. The Book of Tea edited by Lu Yu is the first monograph on tea culture in the world, which discusses the planting, picking and processing of tea in detail. In animal husbandry, the Tang Dynasty adopted the method of introduction and hybridization, and developed new livestock varieties such as beards and mules. Its scale and achievements were rare in the world at that time, which fully demonstrated the great achievements of ancient livestock breeding science. Edited by Sok Li. It is the earliest and most complete veterinary ceremony in China. There are Zhuge Ying's Planting Method in the Sui Dynasty, Zhaoren's Career by others, Living in Shu Yao by Wang Min, Bao Sheng Yue Ji by Wei Hanggui, Notes on Plants in Pingquan by Li Deyu, Miscellaneous Notes of Youyang by Duan and Lei by Lu Guimeng.

Sui and Tang Dynasties made outstanding geographical achievements and occupied an important position in the geographical history of China and the world. Especially in the compilation of local chronicles, the enrichment of cartography, the overseas expansion of geographical knowledge, and the research and investigation of natural geography such as tidal causes and land-sea changes, it has made obvious progress compared with the previous generation, which has written a glorious chapter for the development of geography in this period. During the great cause of the Sui Dynasty, the court ordered the compilation of local chronicles on a large scale throughout the country. Local chronicles and maps reported all over the country will be compiled into national general maps. For example, local maps and maps are the first national maps compiled by officials in the history of China. In the Tang dynasty, there were officials in charge of maps and maps, and it was stipulated that all States and governments in the country should compile maps and maps every three years. At that time, more than 50 States had maps and maps, and the national maps and maps also had new development. Among them, Xiao Deyan's Outlooks, Li Jifu's Map of Yuanhe County, Jia Dan's Four Nations in Guxian County, and Kong Shurui's Geography are all excellent. During Yang Di's reign, Pei Ju was ordered to be in charge of the trade in the western regions, recording the landforms and customs of the countries in the region, drawing them into an atlas and writing the Map of the Western Regions; In the early Tang Dynasty, Wang Xuance went to India for three times, and when he came back, he wrote Biography of the Western Regions. During the Zhenguan period, Xuanzang went west to learn the law, and after he came back, he wrote the "Datang Western Regions"; During the Tianbao period, Du Huan stayed in Dashi for 10 years, and later wrote "Beijing-Hangzhou Ji"; In the third year of Tianfu at the end of Jin Dynasty, Gao Juhai wrote travel notes. The appearance of these records not only makes cartography develop rapidly, but also fills the gap in foreign geography. In addition, the administrative division map and military map of the Tang Dynasty also made a breakthrough, which became the masterpiece of ancient geography in China. China has a vast coastline, so the prevention and utilization of tidal disasters are very important. On the basis of years of observation and research, Dou wrote. Yan Feng also studied the tidal phenomenon. When talking about tides, he described in detail the law of tides passing day by day. Yan Zhenqing's Fairy Altar in Magu Mountain, Nancheng County, Fuzhou, and Bai Juyi's Tide Fu vividly record the understanding of the land and sea changes in the Tang Dynasty. The investigation of the source of the Yellow River and the understanding of natural geography such as underground karst topography, coastal topography and desert topography have made scientific conclusions.

The medical achievements in Sui and Tang Dynasties are still widely known. The General Theory of Diseases and Syndrome written by Chao, a famous doctor in Sui Dynasty, describes the causes, diagnosis, treatment and prevention methods of many diseases, which reflects that the medicine in Sui Dynasty has reached a quite high level. At that time, intestinal anastomosis, vascular ligation, tooth extraction and other surgical operations were unprecedented in the world. Sun Simiao was a famous physician in Tang Dynasty, who devoted his life to medicine. The New Materia Medica compiled by him in Tang Gaozong is known as the "King of Medicine" and is the first pharmacopoeia promulgated by the state in the world. By the Tang Dynasty, acupuncture had reached a fairly high level, and a large number of acupuncture wall charts, maps and monographs appeared, and acupuncture therapy was formally included in the national medical education curriculum. In addition, during the Sui and Tang Dynasties, the medical system was perfected, medical classics were systematically sorted out and deeply studied, and medicine was scientifically divided.

The achievements of water conservancy in Sui and Tang Dynasties were outstanding. The Grand Canal, which connects five major water systems, goes down in history with its grand scale and superb design level. Fuling Shi Yu is the earliest water level station in China. Irrigation from the Yellow River in Tang Dynasty and the restoration and transformation of irrigation system in Guanzhong Plain have scientifically solved major problems such as water diversion, drainage and irrigation, and provided valuable experience for human water conservancy.

The architectural technology in Sui and Tang Dynasties made brilliant achievements. Daxing City and Luoyang City, which were built by Yuwen Kai, a famous architect in Sui Dynasty, and Chang 'an City, which was carefully planned and expanded in Tang Dynasty, have reasonable design ideas and large-scale buildings. The functions of palaces, houses, workshops, markets, streets, water sources, shipping, greening, etc. have greatly surpassed the previous capitals and have had a far-reaching impact. Zhao Zhouqiao still remains in the history of bridge architecture with its peculiar modeling and exquisite design.