Abstract: Time-resolved fluorescence assay is a new nonisotopic and ultrasensitive detection method of using lanthanide chelate as detectable label and detect lanthanide chelate fluorescence, having a great prospect. In recent years, a serial of assay systems have been developed quickly and have more sensitivity, such as enzyme-amplified time-resolved fluorescence assay, time-resolved quenching assay and molecular beacon. They fit for more different requirement, and have been gotten a broader application in clinical diagnosis and science research.