Highly stable water-soluble NIR-II nanofluorescent probe material with highly efficient NIR-II luminescence properties and its luminescence wavelength extending up to 1700 nm. Live bioimaging confirmed that the fluorescent probe enables high resolution visualization of systemic blood vessels as well as the in situ liver cancer system. In addition, the probe also performed high-speed imaging of various tumors, such as brain vascular imaging and hemodynamics, and achieved considerable cerebral angiography performance.