Abstract: 【Objective】 To investigate the volatile components and polyphenol compositions in the peels of two new ⁶⁰Co-γ ray-induced mutant kumquat germplasms， Cuixiang No.1 and Fule kumquat， so as to provide theoretical basis for evaluation and utilization of new kumquat germplasms as well as the exploitation and application of functional components.【Method】 Peels of Rong’an kumquat and its mutant Cuixiang No.1， Huapi kumquat and its mutant Fule kumquat were used as materials. The volatile components were determined by gas chromatography-mass spectrometry（GC-MS）， identified by comparing ion information with the NIST20 mass spectral database， and their relative contents were calculated using the peak area normalization method. The flavor intensity of volatile components was evaluated by the relative odor activity value（ROAV）， and key flavor compounds and important modified flavor compounds were screened. Total phenolic and flavonoid contents in peel samples of four kumquat germplasms were determined by Folin-Ciocalteu colori-metry. Polyphenol compositions were analyzed by ultra-high performance liquid chromatography-quadrupole-Orbitrap mass spectrometry（UHPLC-Q-Orbitrap-MS）， and correlation analysis was performed.【Result】 A total of 96 volatile components were detected in the peels of the four kumquat germplasms. Cuixiang No.1 and Rong’an kumquat shared 85 volatile components， both dominated by hydrocarbons， and followed by esters； their common major volatiles included D-limonene， myrcene，（+）-α-pinene， and terpinolene. In addition， germacrene D was a major volatile in Rong’an kumquat peel. Fule kumquat and Huapi kumquat shared 73 volatile components， both dominated by hydrocarbons and followed by aldehydes； their common major volatiles were D-limonene and myrcene. Moreover， trans-2-hexenal was a major volatile unique to Fule kumquat. ROAV results revealed that Cuixiang No.1 and Rong’an kumquat shared eight key flavor compounds including（+）-α-pinene and myrcene， while Fule kumquat and Huapi kumquat shared seven key flavor compounds including（+）-α-pinene and myrcene. Linalool was the unique key flavor compound of Fule kumquat. The total phenolic content in Fule kumquat peel was significantly lower than that in Huapi kumquat（P<0.05， the same below）. The flavonoid content in Cuixiang No.1 peel was significantly lower than that in Rong’an kumquat. The four germplasms possessed identical phenolic acid compositions， with phthalic acid and trans-ferulic acid as the main phenolic acids. In Cuixiang No.1 and Rong’an kumquat， quercetin-3-O-glucoside was the most abundant flavonoid， with contents of 13.865 and 9.733 ng/100 mg respectively； kaempferol and quercetin were unique to Cuixiang No.1. In Fule kumquat and Huapi kumquat， the main flavonoids were vitexin， quercetin-3-O-glucoside， and isorhamnetin， with quercetin unique to Fule kumquat. Correlation analysis showed that total phenolic content was extremely significantly and positively correlated with flavonoid content（P<0.001）. Kaempferol content was extremely significantly and positively correlated with vanillin content （P<0.001）， and extremely significantly and positively correlated with quercetin-3-O-glucoside， luteolin， and quercetin （P<0.01）.【Conclusion】 The new mutant germplasms Cuixiang No.1 and Fule kumquat induced by ⁶⁰Co-γ ray are rich in volatile components and polyphenolic compounds. Compared with the original germplasms， the two new germplasms exhibit superior fruit flavor quality and contents of important bioactive components， showing promising potential for deve-lopment and application.