Abstract: Radiofrequency cold plasma-assisted extraction technique was used to efficiently extract anthocyanins from purple maize cobs. The pretreatment parameters such as discharge power, pretreatment time and working air pressure were determined by single factor and response surface analysis experiments. Meanwhile, the composition of anthocyanins from purple corn kernel was analysed and identified using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS). The antioxidant properties of the extracted anthocyanins were also evaluated using Caenorhabditis elegans and chemical reagents, respectively. The results showed that the optimal conditions for cold plasma pretreatment were: discharge power of 127 W, processing time of 75 s, and working pressure of 150 Pa. The highest yield of anthocyanins reached (4.05±0.05) mg/g of corncob, which was 49.45% and 28.98% higher than that of the conventional solvent extraction(CSE) method and ultrasonic-assisted extraction(UAE) method, respectively. Anthocyanins in purple corncob were mainly composed of pelargonidin-3-O-glucoside, cyanidin-3-O-glucoside, cyanidin and petunidin-3-O-glucoside. Compared with CSE and UAE methods, the content of anthocyanins changed by cold plasma pretreatment. The content of pelargonidin-3-O-glucoside decreased, while the content of cyanidin-3-O-glucoside increased. Anthocyanins from purple maize cobs scavenged DPPH and ABTS radicals with half maximal inhibitory concentration (IC50) of 0.2972 and 0.2770 mg/mL, respectively, which were were similar to the free radical scavenging ability of ascorbic acid. By feeding anthocyanins to C.elegans, they showed some excellent physiological behaviours such as 29.26% longer average life span, 26.25% higher antioxidant capacity and 60.83% lower reactive oxygen species levels.