Abstract: In order to obtain a more reliable primary core germplasm population of Camellia yungkiangensis, strengthen the breeding, development and utilization of Camellia yungkiangensis germplasm and molecular genetics research, solve the problem of high conservation cost of its germplasm resources, and promote the identification and effective utilization of Camellia yungkiangensis germplasm resources. Using 118 Camellia yungkiangensis germplasm resources as materials, a total of 23 agronomic traits including 19 phenotypic traits and 4 basic quality components were analyzed; Based on two Genetic distance (standardized Euclidean distance, Mahalanobis distance), four clustering methods (sum of squares of deviations, unweighted group average, longest distance, shortest distance) and seven overall sampling scales (10%, 15%, 20%, 25%, 30%, 35%, 40%), 56 candidate core collections of Camellia yungkiangensis were constructed, and the primary core collection was constructed using the best construction scheme selected. Evaluate the representativeness of core germplasm by analyzing the phenotypic genetic diversity and degree of variation of original germplasm, preserved germplasm, and core germplasm, as well as t-tests between various qualitative and quantitative traits, and confirm the core germplasm using principal component analysis. When constructing the core collection of Camellia yungkiangensis, the standardized Euclidean distance was better than Mahalanobis distance in the two Genetic distance; Among the four clustering methods, the shortest distance method is superior to the other three; Among the 7 overall sampling scales, a sampling ratio of 30% is more suitable for the construction of core germplasm of Camellia yungkiangensis. The analysis and evaluation of the 38 core germplasm constructed showed that the core germplasm had good consistency with the 6 characteristic values of the 23 traits of the original germplasm, and the genetic diversity index had a certain degree of improvement; The t-test results showed that the core germplasm balanced the distribution of rare traits and effectively preserved the genetic diversity of the original germplasm; The results of principal component analysis showed that the cumulative contribution rate of principal components in core germplasm was higher than that in original germplasm; When further confirming the core germplasm, it was found that the core germplasm was evenly distributed within the original germplasm range without overlap, effectively avoiding redundancy of the core germplasm. The core germplasm resources of Camellia yungkiangensis constructed can effectively represent the original germplasm, while preserving the traits, genetic diversity, and variation of the original germplasm. The construction strategies of standardized Euclidean distance, shortest distance method, and 30% overall sampling scale are the best methods for constructing core germplasm of Camellia yungkiangensis. Finally, 38 primary core germplasm resources of Camellia yungkiangensis were constructed, accounting for 32.20% of the original germplasm. The evaluation of core germplasm indicates that the construction of primary core germplasm is effective and of high quality, which can fully represent the genetic diversity of the original germplasm while ensuring minimal redundancy.