Abstract:Abstract: Rice germplasm resources are important foundation for rice genetic improvement and new variety breeding. The study of genetic diversity of rice germplasm resources plays an important role in broadening the genetic background of rice. In this study, genetic diversity analysis was conducted on 20 important agronomic traits of 1775 rice germplasm resources from 11 provinces (cities) using multiple analysis methods. The results showed that: The coefficient of variation (CV) of agronomic traits varied greatly, with a ranging from 4.42% (grain thickness) to 89.75% (number of empty grains), There was abundant genetic variation in empty grain number; The range of genetic diversity index (H") was 1.585(number of empty grains) to 2.069(heading date), and the heading stage had rich diversity. Through the analysis of agronomic characters of germplasm from 11 provinces (cities), There was rich diversity in 7 characters such as panicle per plant and spikelets per panicle from Jilin. There were 4 characters such as First heading date, panicle length and so on. Them with rich diversity from Yunnan. While heading stage and other 2 characters were rich from Heilongjiang. The 1775 germplasms included lines, landrace and advanced cultivar. The 11 characters were bundant such as leaf length and plant height in landrace, and the 9 characters were abundant such as First heading date and panicle per plant of advanced cultivar. Genetic diversity analysis of different geographical sources and germplasm types can provide useful information for the selection of parental material and thus help in planning breeding strategies. The correlation analysis showed that 149 correlation coefficients reached the very significant level (P < 0.01), among which 3 growth stage traits, such as head stage, had higher correlation with other agronomic traits. Principal component analysis found that the cumulative contribution rate of the first 6 principal components reached 79.309%, and the contribution rate was the largest in the traits related to growth period. The 1775 rice germplasm can be divided into three groups at the Euclidean genetic distance of 0.6, among which the germplasm was group I from three provinces in Northeast China, Beijing and Hangzhou.10 traits were rich, including the growth stage traits, the number of tillers related to yield and the panicle per plant. It can provide excellent germplasm for rice germplasm resource innovation and new variety breeding in the future. Group II only included Ningxia, indicating that germplasm resources in Ningxia were far from germplasm resources in other provinces (cities). Therefore, the utilization rate of those germplasms should be increased to broaden the genetic basis of rice germplasm resources. Group III includes Hebei, Shandong, Yunnan, Jiangsu and Xinjiang, The H " of grain length is the largest among the three groups, indicating that the grain length is rich in the germplasms, which can provide rich germplasm for rice quality breeding in the future.