The overall objective of this work was to identify and determine the controlling factors of catalytic activity of CeO2 nanoparticles with different properties. Therefore, four kinds of CeO2 nanoparticles are successfully synthesized and used as peroxidase mimics. The results reveal that the catalytic activity is related to specific surface area and surface oxygen (O-sur) content. For different CeO2 nanoparticles, specific surface area is the leading factor of catalytic activity. The catalytic activity increases with the increasing specific surface area. If the CeO2 nanoparticles have similar specific surface area, the less O-sur contains, the lower catalytic activity will be. Meanwhile, crystallinity is not the influence factor of catalytic activity. Bamboo-like CeO2 (B-CeO2) nanoparticles show excellent catalytic activity and the reaction conditions are optimized. Furthermore, the catalytic activity of B-CeO2 nanoparticles decreases very slightly after 15 cycles of the catalysis experiment. Therefore, B-CeO2 nanoparticles can serve as effective recyclable peroxidase mimics.