Pomelo peel is a kind of medicinal biomass resource rich in essential oil,but its essential oil composition and biological activity have not been deeply studied.In this paper,12 different varieties of pomelo peelessential oils were extracted by steam distillation,and then the essential oil components and relative contents were determined by gas chromatography-mass spectrometry (GC-MS).Then the antioxidant and antibacterial activities of different varieties of pomelo peel essential oils were compared by DPPH radical scavenging method and filter paper method.Finally,principal component analysis and cluster analysis were performed on the GC-MS analysis data of different varieties of pomelo peel essential oils,and combined with the results of antioxidant and antibacterial experiments,the relationship between the components of pomelo peel essential oils and their antioxidant and antibacterial abilities was clarified.The results showed that the extraction rate of essential oil was 0.22%-1.52%.Thirty-five chemical components,such as D-limonene,β-laurene,α-pinene,α-aquinene and linalool,were identified from different varieties of pomelo peel essential oil by GC-MS.DPPH scavenging experiment showed that the antioxidant capacity of pomelo peel essential oil was positively correlated with the concentration of essential oil.The experimental results of filter paper showed that pomelo peel essential oil had a certain antibacterial effect,and the antibacterial effect was more obvious to specific strains.The results of principal component analysis and cluster analysis showed that D-limonene,citral and linalool had significant antioxidant and bacteriostatic effects,while caryophyllene,geranylenol and α-hydroconene also had certain antioxidant and bacteriostatic abilities.