Vanadium flow battery (VFB) holds great promise for use in large scale energy storage applications. However, one major issue that limits the battery performance is the energy storage capacity loss due to insufficient use of electrolyte. The battery structure design is flexible and acceptable to solve the issue. Based on the mass transport limitation of the conventional rectangular vanadium flow battery (RFB), a novel circular vanadium flow battery (CFB) was firstly proposed in the research. Without increasing pump consumption, the new structure of CFB is effective to achieve mass transport enhancement and concentration polarization reduction. The charge–discharge test confirmed the performance advantage of CFB, presenting a significant increment of 10.52% at 40 mA cm−2 and 30.46% at 160 mA cm−2 in the utilization of electrolyte and improved energy storage capacity by 12.56% at 40 mA cm−2 and a 2.55 times of that for RFB at 160 mA cm−2. The performance advantage of CFB becomes exceptionally evident at high current densities.