Carbon monoxide (CO) is a vital intracellular gas messenger known for its cytoprotective and homeostatic properties. It plays a pivotal role in a myriad of biological processes. Therefore, the precise detection of CO is of paramount importance in unraveling the intricacies of pathological mechanisms and advancing the development of disease diagnosis. We herein introduce NFCOP, a state-of-the-art near-infrared (NIR) turn-on fluorescence (FL) probe that has been meticulously designed for highly sensitive, swift and selective imaging of CO. The NFCOP response occurred rapidly with CO, within just 10 s, and the calculated detection limit for CO was determined to be 0.32 μmol/L. Further investigations conducted at the cellular level and in vivo demonstrated that NFCOP possesses high sensitivity and selectivity for imaging CO.