【Objective】The objective of this study is to evaluate some major phenotypic characteristics diversity of mandarin germplasms and explore the comprehensive method for screening important mandarin germplasm resources. 【Method】The diversity evaluation of 18 phenotypic traits in 239 mandarin accessions were carried out. Variation coefficients, Shannon-Weaver Information index cluster analysis, principal component analysis, correlation and regression analysis were comprehensively used to evaluate the relationshi...