Reactive oxygen species (ROS) are generated in the body and related to many pathophysiological processes. Hence, detection of ROS is indispensable in understanding, diagnosis, and treatment of many diseases. Here, near-infrared (NIR) chemiluminescent (CL) carbon nanodots (CDs) are fabricated for the first time and their CL quantum yield can reach 9.98 × 10 einstein mol, which is the highest value ever reported for CDs until now. Nanointegration of NIR CDs and peroxalate (P-CDs) through the bridging effect of amphiphilic triblock copolymer can serve as turn-on probes for the detection and imaging of hydrogen peroxide (HO). Considering high efficiency and large penetration depth of NIR photons, the P-CDs are employed in bioimaging HO in vitro and in vivo, and the detection limit can reach 5 × 10 m, among the best reported of CDs-based sensors. Moreover, imaging of inflammatory HO in a mouse model of peritonitis is achieved by employing the P-CDs as sensors. The results may provide a clue for the diagnosis and treatment of inflammation or cancers employing CL CDs as sensors.