To prepare electrode materials with excellent comprehensive properties for supercapacitor applications, and to promote the reuse of waste fruit peels. This work used waste pomelo peel as a carbon source for high-temperature carbonization, and a series of porous biomass carbon materials (YB-K) was prepared using a combination of freeze-drying and activation pore-making. The relationship between the structure of YB-K materials and the amount of activator was investigated by characterization. The results show that the YB-K materials (YB-K5) with the mass ratio of raw materials to activator of 1:5 have the best overall properties, and their specific surface area is as high as 1277.14 m2/g. Notably, the YB-K5 materials can be doped with nitrogen to prepare electrode materials (YB-K5-N) with excellent electrochemical properties. The specific capacitance of YB-K5-N electrode materials reaches 247.26 F/g at 0.5 A/g current density. Importantly, the YB-K5-N symmetric (button type) supercapacitor assembled with YB-K5-N materials showed good cycling stability with 87.58% specific capacitance retention after 3000 cycles. The YB-K5-N electrode materials prepared in this work have potential applications in energy conversion, energy storage and electrochemistry, which provide a new idea for utilizing waste fruit peels.