Abstract: Cuscuta Semen samples were crushed, extracted with 75% (volume fraction) ethanol solution, purified with AB-8 type macroporous resin, and diluted with 80% (volume fraction) methanol solution. Ultra-high performance liquid chromatography (UHPLC) combined with a similarity evaluation system was used to establish characteristic chromatograms of the estrogen-like effect active site group of 10 Cuscuta Semen from different regions, as well as qualitative and quantitative methods for common key active components. Softwares of SPSS 19.0 and Origin 2017 were used for performing cluster analysis and principal component analysis on the peak areas of common key active components, to screen for quality evaluation index components. It was shown that a total of 8 common characteristic peaks were identified through the characteristic chromatograms of 10 samples. By comparing with the reference standard, it was determined that the key active components with estrogen-like effects in Cuscuta Semen, including hyperoside, isoquercitrin, astragalin, quercitrin, quercetin, apigenin, kaempferol, and isorhamnetin were identified. RSDs (n=10) of the relative retention time (vs. quercetin) of these components less than 1.0%, indicating that the active components in samples from different origins showed good consistency. Linear relationships between the mass concentrations and corresponding peak areas of 8 components were kept in definite ranges, with detection limits (3S/N) in the range of 0.001 0—0.003 0 g · L⁻¹, RSDs (n=6) of the determined values less than 4.0%, and recoveries obtained by standard addition method in the range of 94.1%-98.9%. As found by results of cluster analysis and principal component analysis, samples of Cuscuta Semen from 10 regions could be divided into 5 categories. The cumulative variance contribution rate of hyperoside, isoquercitrin, astragalin, and quercitrin was 99.274 74%, which could comprehensively characterize the information of Cuscuta Semen medicinal materials and be used as quality evaluation indicators.